Rung 21: a carrier's growth limit binds its non-generator builds — a storage unit and two stores over two periods¶
One rung of the PyPSA corpus: the file pypsa.yaml projected onto what this network builds, attached to that network, and held to what PyPSA solves it to.
✔ Verified against pypsa master at 51986084 — objective 8452.5 on both sides; structure ✔ 18 constraints · 8 variables, name for name; size ✔ 74 rows · ✔ 35 columns · ✔ 134 nonzeros; duals ✔ 74 rows, 2 negated; model for model: 26 blocks equal, 0 documented splits, 1 recorded deviations.
Rows and columns, PyPSA against specsolve, name for name
| row | PyPSA | specsolve |
|---|---|---|
Bus-nodal_balance |
4 | 4 |
Carrier-growth_limit |
2 | 2 |
Generator-fix-p-lower |
8 | 8 |
Generator-fix-p-upper |
8 | 8 |
StorageUnit-energy_balance |
4 | 4 |
StorageUnit-ext-p_dispatch-lower |
4 | 4 |
StorageUnit-ext-p_dispatch-upper |
4 | 4 |
StorageUnit-ext-p_nom-lower |
1 | 1 |
StorageUnit-ext-p_nom-upper |
1 | 1 |
StorageUnit-ext-p_store-lower |
4 | 4 |
StorageUnit-ext-p_store-upper |
4 | 4 |
StorageUnit-ext-state_of_charge-lower |
4 | 4 |
StorageUnit-ext-state_of_charge-upper |
4 | 4 |
Store-energy_balance |
6 | 6 |
Store-ext-e-lower |
6 | 6 |
Store-ext-e-upper |
6 | 6 |
Store-ext-e_nom-lower |
2 | 2 |
Store-ext-e_nom-upper |
2 | 2 |
| column | PyPSA | specsolve |
|---|---|---|
Generator-p |
8 | 8 |
StorageUnit-p_dispatch |
4 | 4 |
StorageUnit-p_nom |
1 | 1 |
StorageUnit-p_store |
4 | 4 |
StorageUnit-state_of_charge |
4 | 4 |
Store-e |
6 | 6 |
Store-e_nom |
2 | 2 |
Store-p |
6 | 6 |
The model¶
The same model, as math
A plain n.optimize(), and its multi-period and stochastic classes, in one file. Every second-stage quantity spans a scenario (a future dispatch is chosen in) and every asset stands in the investment periods its build year and lifetime span. A parameter spans scenario exactly when PyPSA reads it per scenario. Capacity is chosen once, before the future is known, and paid once per active period at its cost in expectation over the scenarios; operation is the expectation over the scenarios' weights, with a share priced at the tail through the CVaR rows, which stand only where a risk preference is set. A plain run feeds one scenario, one period, all-active masks and unit weights, and the model collapses to the standard one. A security-constrained run copies each branch flow limit once per outage in an outage set that a plain run leaves empty. Which snapshots an asset is active in, a scenario's weight, and the outage factors are data prep.
Sets¶
| Symbol | Meaning |
|---|---|
| \(\Xi\) | index \(\xi\) — scenario — the futures dispatch is chosen in, each with a weight |
| \(\mathcal{T}\) | index \(t\) — snapshot with \(\mathrm{snapshot\_period}: \mathcal{T} \to \mathcal{Y}\) — dispatch periods |
| \(\mathcal{N}\) | index \(n\) — bus with \(\mathrm{Generator\_bus}: \mathcal{G} \to \mathcal{N},\ \mathrm{Link\_output\_bus}: \mathcal{O} \to \mathcal{N},\ \mathrm{Process\_output\_bus}: \mathcal{R} \to \mathcal{N},\ \mathrm{Load\_bus}: \mathcal{D} \to \mathcal{N},\ \mathrm{StorageUnit\_bus}: \mathcal{S} \to \mathcal{N},\ \mathrm{Store\_bus}: \mathcal{V} \to \mathcal{N}\) — network nodes |
| \(\mathcal{G}\) | index \(g\) — generator with \(\mathrm{Generator\_bus}: \mathcal{G} \to \mathcal{N}\) — generating units, each on one bus |
| \(\mathcal{L}\) | index \(l\) — link with \(\mathrm{Link\_output\_link}: \mathcal{O} \to \mathcal{L}\) — controllable connections, each from one bus to the buses it delivers to |
| \(\mathcal{O}\) | index \(o\) — link_output with \(\mathrm{Link\_output\_link}: \mathcal{O} \to \mathcal{L},\ \mathrm{Link\_output\_bus}: \mathcal{O} \to \mathcal{N}\) — a link's output ports, one label per port a link declares — PyPSA's bus1, bus2, … columns read long, so a link of any number of output ports is one term in the balance, data prep |
| \(\mathcal{J}\) | index \(j\) — process with \(\mathrm{Process\_output\_process}: \mathcal{R} \to \mathcal{J}\) — generalized multi-port converters, each with an internal power that every port draws or delivers at its own rate |
| \(\mathcal{R}\) | index \(r\) — process_output with \(\mathrm{Process\_output\_process}: \mathcal{R} \to \mathcal{J},\ \mathrm{Process\_output\_bus}: \mathcal{R} \to \mathcal{N}\) — a process's ports, one label per port a process declares — PyPSA's bus0, bus1, … each carry a signed rate, so a process of any number of ports is one term in the balance, data prep |
| \(\mathcal{D}\) | index \(d\) — load with \(\mathrm{Load\_bus}: \mathcal{D} \to \mathcal{N}\) — demands, each on one bus |
| \(\mathcal{S}\) | index \(s\) — storage_unit with \(\mathrm{StorageUnit\_carrier}: \mathcal{S} \to \mathcal{I},\ \mathrm{StorageUnit\_bus}: \mathcal{S} \to \mathcal{N}\) — storage units, dispatch and store behind one bus connection |
| \(\mathcal{V}\) | index \(v\) — store with \(\mathrm{Store\_carrier}: \mathcal{V} \to \mathcal{I},\ \mathrm{Store\_bus}: \mathcal{V} \to \mathcal{N}\) — pure energy stores, each on one bus |
| \(\mathcal{Y}\) | index \(y\) — period with \(\mathrm{snapshot\_period}: \mathcal{T} \to \mathcal{Y}\) — investment periods — PyPSA's investment_periods |
| \(\mathcal{I}\) | index \(i\) — carrier with \(\mathrm{StorageUnit\_carrier}: \mathcal{S} \to \mathcal{I},\ \mathrm{Store\_carrier}: \mathcal{V} \to \mathcal{I}\) — energy carriers, what a growth limit is set per |
Parameters¶
| Symbol | Meaning |
|---|---|
| \(\mathrm{w}\) | snapshot_weightings_objective over \(\mathcal{T}\) — PyPSA's snapshot_weightings.objective — hours a snapshot stands for in the cost |
| \(\mathrm{p}^{\mathrm{nom}}\) | Generator_p_nom over \(\Xi \times \mathcal{G}\) — nominal power |
| \(\mathrm{ext}\) | Generator_p_nom_extendable over \(\mathcal{G}\) — whether the nominal power is a decision |
| \(\underline{\mathrm{p}}\) | Generator_p_min_pu over \(\Xi \times \mathcal{T} \times \mathcal{G}\) — least output, per unit of nominal power |
| \(\overline{\mathrm{p}}\) | Generator_p_max_pu over \(\Xi \times \mathcal{T} \times \mathcal{G}\) — most output, per unit of nominal power — an availability profile |
| \(\mathrm{c}\) | Generator_marginal_cost over \(\Xi \times \mathcal{T} \times \mathcal{G}\) — cost of one unit of output |
| \(\mathrm{c}^{(2)}\) | Generator_marginal_cost_quadratic over \(\Xi \times \mathcal{T} \times \mathcal{G}\) — cost of the square of one unit of output |
| \(\mathrm{sgn}\) | Generator_sign over \(\mathcal{G}\) — the sign output enters its bus's balance with — PyPSA's sign, 1 unless given, -1 for a unit that draws power. PyPSA refuses one that differs by scenario (constants.py:43) |
| \(\mathrm{com}\) | Generator_committable over \(\mathcal{G}\) — whether output is gated by an on/off status decision |
| \(\eta\) | Link_efficiency over \(\Xi \times \mathcal{T} \times \mathcal{O}\) — share of the flow that arrives at an output port, PyPSA's efficiency, efficiency2, … read long — negative where that port consumes rather than delivers. Read at the snapshot the flow arrives, so a delayed port delivers at its arrival snapshot's efficiency (constraints.py:1498) |
| \(\mathrm{d}^{f}\) | Link_output_delay over \(\mathcal{O}\) — snapshots a port's delivery lags its link's flow — PyPSA's delay, delay2, … read long, divided by the snapshot_weightings.generators value and rounded up in data prep; zero for a port that delivers at once. A port has the same delay in every scenario, because PyPSA refuses a delay that differs by scenario (constants.py:52) |
| \(\mathrm{cyc}^{f}\) | Link_output_cyclic_delay over \(\mathcal{O}\) — whether a delayed port's flow wraps from the end of its investment period — PyPSA's cyclic_delay, cyclic_delay2, …; where it does not, the flow still in transit at each period's first snapshots is lost. The flag is the same in every scenario, as the delay is |
| \(\alpha\) | Process_rate over \(\Xi \times \mathcal{T} \times \mathcal{R}\) — the energy a port draws or delivers per unit of internal power, PyPSA's rate0, rate1, … read long — negative where the port withdraws, positive where it injects; a link is a process whose bus0 rate is minus one and whose output rates are its efficiencies. Read at the snapshot the transfer arrives, so a delayed port transfers at its arrival snapshot's rate (constraints.py:1498) |
| \(\mathrm{d}^{z}\) | Process_output_delay over \(\mathcal{R}\) — snapshots a port's transfer lags its process's internal power — PyPSA's delay0, delay1, … read long, divided by the snapshot_weightings.generators value and rounded up in data prep; zero for a port that transfers at once. A port has the same delay in every scenario, as a link's port has |
| \(\mathrm{cyc}^{z}\) | Process_output_cyclic_delay over \(\mathcal{R}\) — whether a delayed port's transfer wraps from the end of its investment period — PyPSA's cyclic_delay0, cyclic_delay1, …; where it does not, the energy still in transit at each period's first snapshots is lost. The flag is the same in every scenario, as the delay is |
| \(\mathrm{load}\) | Load_p_set over \(\Xi \times \mathcal{T} \times \mathcal{D}\) — demand |
| \(\mathrm{sgn}^{\mathrm{load}}\) | Load_sign over \(\mathcal{D}\) — the sign a load's demand enters its bus's balance with — PyPSA's sign, -1 unless given, 1 for a load that feeds its bus. PyPSA refuses one that differs by scenario (constants.py:43) |
| \(\mathrm{on}^{\mathrm{load}}\) | Load_active over \(\mathcal{D}\) — whether a load stands in the model — PyPSA's active. A load has no build year and no lifetime, so the flag holds in every snapshot. PyPSA refuses one that differs by scenario (constants.py:51) |
| \(\pi\) | scenario_weight over \(\Xi\) — PyPSA's scenario_weightings.weight — the probability of a future |
| \(\mathrm{w}^{y}\) | period_weight_objective over \(\mathcal{Y}\) — PyPSA's investment_period_weightings.objective — what a period's cost weighs; PyPSA reads it only under multi_investment_periods, so data prep feeds one otherwise, whatever the column holds (optimize.py:205-207, :264-266) |
| \(\mathrm{on}\) | Generator_active over \(\mathcal{T} \times \mathcal{G}\) — whether a generator stands in a snapshot's period — PyPSA's active, from build year and lifetime, data prep |
| \(\mathrm{on}^{f}\) | Link_active over \(\mathcal{T} \times \mathcal{L}\) — whether a link stands in a snapshot's period — PyPSA's active, data prep |
| \(\mathrm{on}^{h}\) | StorageUnit_active over \(\mathcal{T} \times \mathcal{S}\) — whether a storage unit stands in a snapshot's period — PyPSA's active, data prep |
| \(\mathrm{on}^{e}\) | Store_active over \(\mathcal{T} \times \mathcal{V}\) — whether a store stands in a snapshot's period — PyPSA's active, data prep |
| \(\mathrm{on}^{z}\) | Process_active over \(\mathcal{T} \times \mathcal{J}\) — whether a process stands in a snapshot's period — PyPSA's active, data prep |
| \(\mathrm{act}^{h}\) | StorageUnit_active_asset over \(\mathcal{S}\) — whether a storage unit is one of PyPSA's active_assets — its active flag alone, without build year and lifetime, so a unit that stands in no snapshot of the horizon still counts. PyPSA refuses one that differs by scenario (constants.py:51) |
| \(\mathrm{act}^{e}\) | Store_active_asset over \(\mathcal{V}\) — whether a store is one of PyPSA's active_assets — its active flag alone, without build year and lifetime, so a unit that stands in no snapshot of the horizon still counts. PyPSA refuses one that differs by scenario (constants.py:51) |
| \(\mathrm{W}^{h}\) | StorageUnit_capital_weight over \(\mathcal{S}\) — the sum of period weights a storage unit stands in — PyPSA's active * period_weighting, summed, data prep |
| \(\mathrm{W}^{e}\) | Store_capital_weight over \(\mathcal{V}\) — the sum of period weights a store stands in — PyPSA's active * period_weighting, summed, data prep |
| \(\mathrm{new}^{h}\) | StorageUnit_first_active over \(\mathcal{Y} \times \mathcal{S}\) — one in the first period a storage unit stands in, zero elsewhere, data prep. PyPSA takes active & (active.cumsum() == 1) (global_constraints.py:265) |
| \(\mathrm{new}^{e}\) | Store_first_active over \(\mathcal{Y} \times \mathcal{V}\) — one in the first period a store stands in, zero elsewhere, data prep. PyPSA takes active & (active.cumsum() == 1) (global_constraints.py:265) |
| \(\overline{\Delta}\) | Carrier_max_growth over \(\mathcal{I}\), neutral where the data has no row — most capacity of a carrier that may be added in a period; no value means no limit. The least over the scenarios, as PyPSA takes it (global_constraints.py:227-231), data prep. PyPSA reads it only under multi_investment_periods (global_constraints.py:220-221), so data prep feeds no value otherwise |
| \(\mathrm{r}\) | Carrier_max_relative_growth over \(\mathcal{I}\) — share of the previous period's additions that may be added on top — the least over the scenarios, as PyPSA takes it, data prep |
| \(\mathrm{w}^{\mathrm{sto}}\) | snapshot_weightings_stores over \(\mathcal{T}\) — PyPSA's snapshot_weightings.stores — hours a snapshot stands for in a storage balance |
| \(\underline{\mathrm{h}}^{\mathrm{nom}}\) | StorageUnit_p_nom_min over \(\Xi \times \mathcal{S}\) — least nominal power an extendable storage unit may be built at |
| \(\overline{\mathrm{h}}^{\mathrm{nom}}\) | StorageUnit_p_nom_max over \(\Xi \times \mathcal{S}\) — most nominal power an extendable storage unit may be built at |
| \(\mathrm{c}^{\mathrm{cap},h}\) | StorageUnit_capital_cost over \(\Xi \times \mathcal{S}\) — cost of one unit of nominal power for the modelled horizon — PyPSA's periodized_cost: overnight_cost as an annuity over lifetime at discount_rate, times nyears, where it is given, and capital_cost where it is not, plus fom_cost (components.py:1126-1147, costs.py:102-203), data prep |
| \(\underline{\mathrm{e}}^{\mathrm{nom}}\) | Store_e_nom_min over \(\Xi \times \mathcal{V}\) — least nominal capacity an extendable store may be built at |
| \(\overline{\mathrm{e}}^{\mathrm{nom}}\) | Store_e_nom_max over \(\Xi \times \mathcal{V}\) — most nominal capacity an extendable store may be built at |
| \(\mathrm{c}^{\mathrm{cap},e}\) | Store_capital_cost over \(\Xi \times \mathcal{V}\) — cost of one unit of nominal capacity for the modelled horizon — PyPSA's periodized_cost: overnight_cost as an annuity over lifetime at discount_rate, times nyears, where it is given, and capital_cost where it is not, plus fom_cost (components.py:1126-1147, costs.py:102-203), data prep |
| \(\mathrm{ext}^{h}\) | StorageUnit_p_nom_extendable over \(\mathcal{S}\) — whether the nominal power is a decision |
| \(\underline{\mathrm{h}}\) | StorageUnit_p_min_pu over \(\Xi \times \mathcal{T} \times \mathcal{S}\) — most storing, per unit of nominal power and negated |
| \(\overline{\mathrm{h}}\) | StorageUnit_p_max_pu over \(\Xi \times \mathcal{T} \times \mathcal{S}\) — most dispatch, per unit of nominal power |
| \(\mathrm{T}^{h}\) | StorageUnit_max_hours over \(\Xi \times \mathcal{S}\) — energy capacity, as hours of dispatch at nominal power |
| \(\eta^{-}\) | StorageUnit_efficiency_store over \(\Xi \times \mathcal{T} \times \mathcal{S}\) — share of the power drawn from the bus that becomes charge |
| \(\eta^{+}\) | StorageUnit_efficiency_dispatch over \(\Xi \times \mathcal{T} \times \mathcal{S}\) — share of the charge drawn down that reaches the bus |
| \(\mathrm{sgn}^{h}\) | StorageUnit_sign over \(\mathcal{S}\) — the sign net dispatch enters its bus's balance with — PyPSA's sign, 1 unless given. PyPSA refuses one that differs by scenario (constants.py:43) |
| \(\rho\) | StorageUnit_retention over \(\Xi \times \mathcal{T} \times \mathcal{S}\) — share of charge kept over a snapshot — PyPSA's (1 - standing_loss) ** elapsed hours, data prep |
| \(\mathrm{inflow}\) | StorageUnit_inflow over \(\Xi \times \mathcal{T} \times \mathcal{S}\) — energy arriving per hour, a river into a reservoir |
| \(\mathrm{soc}^{0}\) | StorageUnit_state_of_charge_initial over \(\Xi \times \mathcal{S}\) — charge held before the first snapshot |
| \(\mathrm{cyc}\) | StorageUnit_cyclic_state_of_charge over \(\Xi \times \mathcal{S}\) — whether the horizon closes on itself instead of opening on the initial charge |
| \(\mathrm{cyc}^{y}\) | StorageUnit_cyclic_state_of_charge_per_period over \(\Xi \times \mathcal{S}\) — whether each investment period closes on itself instead of carrying its charge on to the next; it overrides cyclic_state_of_charge and state_of_charge_initial_per_period. PyPSA reads it only under multi_investment_periods, so data prep feeds false otherwise |
| \(\mathrm{reset}\) | StorageUnit_state_of_charge_initial_per_period over \(\Xi \times \mathcal{S}\) — whether each investment period opens on the initial charge instead of carrying the previous period's; PyPSA reads it only under multi_investment_periods, so data prep feeds false otherwise |
| \(\mathrm{open}\) | StorageUnit_opens_late over \(\mathcal{T} \times \mathcal{S}\) — whether a snapshot is the first a storage unit stands in, where that is not the first of the horizon — PyPSA's active.cumsum() == 1 over the snapshots it stands in, past the first snapshot, data prep; false in a run where every unit stands throughout |
| \(\mathrm{idle}\) | StorageUnit_inactive_snapshots over \(\mathcal{S}\) — how many snapshots a storage unit does not stand in — PyPSA's (~active).sum(), data prep. A cyclic unit reaches back this many snapshots further, so it closes on the last snapshot it stands in |
| \(\mathrm{c}^{h}\) | StorageUnit_marginal_cost over \(\Xi \times \mathcal{T} \times \mathcal{S}\) — cost of one unit of dispatch |
| \(\mathrm{c}^{h,(2)}\) | StorageUnit_marginal_cost_quadratic over \(\Xi \times \mathcal{T} \times \mathcal{S}\) — cost of the square of one unit of dispatch; storing is not charged |
| \(\mathrm{c}^{\mathrm{soc}}\) | StorageUnit_marginal_cost_storage over \(\Xi \times \mathcal{T} \times \mathcal{S}\) — cost of one unit of charge held over one snapshot |
| \(\mathrm{ext}^{e}\) | Store_e_nom_extendable over \(\mathcal{V}\) — whether the nominal energy capacity is a decision |
| \(\underline{\mathrm{e}}\) | Store_e_min_pu over \(\Xi \times \mathcal{T} \times \mathcal{V}\) — least energy held, per unit of nominal capacity — negative for a store that may go short |
| \(\overline{\mathrm{e}}\) | Store_e_max_pu over \(\Xi \times \mathcal{T} \times \mathcal{V}\) — most energy held, per unit of nominal capacity |
| \(\mathrm{sgn}^{q}\) | Store_sign over \(\mathcal{V}\) — the sign the power a store delivers enters its bus's balance with — PyPSA's sign, 1 unless given. PyPSA refuses one that differs by scenario (constants.py:43) |
| \(\rho^{e}\) | Store_retention over \(\Xi \times \mathcal{T} \times \mathcal{V}\) — share of energy kept over a snapshot — PyPSA's (1 - standing_loss) ** elapsed hours, data prep |
| \(\mathrm{e}^{0}\) | Store_e_initial over \(\Xi \times \mathcal{V}\) — energy held before the first snapshot |
| \(\mathrm{cyc}^{e}\) | Store_e_cyclic over \(\Xi \times \mathcal{V}\) — whether the horizon closes on itself instead of opening on the initial energy |
| \(\mathrm{cyc}^{e,y}\) | Store_e_cyclic_per_period over \(\Xi \times \mathcal{V}\) — whether each investment period closes on itself instead of carrying its energy on to the next; it overrides e_cyclic and e_initial_per_period. PyPSA reads it only under multi_investment_periods, so data prep feeds false otherwise |
| \(\mathrm{reset}^{e}\) | Store_e_initial_per_period over \(\Xi \times \mathcal{V}\) — whether each investment period opens on the initial energy instead of carrying the previous period's; PyPSA reads it only under multi_investment_periods, so data prep feeds false otherwise |
| \(\mathrm{open}^{e}\) | Store_opens_late over \(\mathcal{T} \times \mathcal{V}\) — whether a snapshot is the first a store stands in, where that is not the first of the horizon — PyPSA's active.cumsum() == 1 over the snapshots it stands in, past the first snapshot, data prep; false in a run where every store stands throughout |
| \(\mathrm{idle}^{e}\) | Store_inactive_snapshots over \(\mathcal{V}\) — how many snapshots a store does not stand in — PyPSA's (~active).sum(), data prep. A cyclic store reaches back this many snapshots further, so it closes on the last snapshot it stands in |
| \(\mathrm{c}^{q}\) | Store_marginal_cost over \(\Xi \times \mathcal{T} \times \mathcal{V}\) — cost of one unit of power delivered |
| \(\mathrm{c}^{q,(2)}\) | Store_marginal_cost_quadratic over \(\Xi \times \mathcal{T} \times \mathcal{V}\) — cost of the square of the net power delivered, so charging costs as much as delivering |
| \(\mathrm{c}^{e}\) | Store_marginal_cost_storage over \(\Xi \times \mathcal{T} \times \mathcal{V}\) — cost of one unit of energy held over one snapshot |
Conditions¶
| Symbol | Meaning |
|---|---|
| \(\mathrm{StorageUnit\_ext}\) | StorageUnit_ext over \(\mathcal{T} \times \mathcal{S}\) — a storage unit with an extendable build that stands in the snapshot's period — PyPSA's ext rows |
Variables¶
| Symbol | Meaning |
|---|---|
| \(p\) | Generator_p over \(\Xi \times \mathcal{T} \times \mathcal{G}\) — Generator-p — output of a generator in a snapshot |
| \(h^{+}\) | StorageUnit_p_dispatch over \(\Xi \times \mathcal{T} \times \mathcal{S}\) — StorageUnit-p_dispatch — power delivered to the bus |
| \(h^{-}\) | StorageUnit_p_store over \(\Xi \times \mathcal{T} \times \mathcal{S}\) — StorageUnit-p_store — power drawn from the bus into charge |
| \(\mathit{soc}\) | StorageUnit_state_of_charge over \(\Xi \times \mathcal{T} \times \mathcal{S}\) — StorageUnit-state_of_charge — energy held at the end of a snapshot |
| \(e\) | Store_e over \(\Xi \times \mathcal{T} \times \mathcal{V}\) — Store-e — energy held at the end of a snapshot |
| \(q\) | Store_p over \(\Xi \times \mathcal{T} \times \mathcal{V}\) — Store-p — power delivered to the bus; charging is negative |
| \(H\) | StorageUnit_p_nom_ext over \(\mathcal{S}\) — StorageUnit-p_nom — nominal power where it is a decision, for a storage unit that is active; the parameter of the same PyPSA name carries the fixed regime |
| \(E\) | Store_e_nom_ext over \(\mathcal{V}\) — Store-e_nom — nominal capacity where it is a decision, for a store that is active; the parameter of the same PyPSA name carries the fixed regime |
| \(f\) | Link_p over \(\Xi \times \mathcal{T} \times \mathcal{L}\) — Link-p — PyPSA's p0, the flow measured at the Link_bus0 end: a positive value withdraws there and injects at every bus the link's output ports deliver to |
| \(z\) | Process_p over \(\Xi \times \mathcal{T} \times \mathcal{J}\) — Process-p — PyPSA's internal power p: a positive value drives every port at its own rate, withdrawing where the rate is negative and injecting where it is positive |
Definitions¶
| Symbol | Meaning |
|---|---|
| \(\mathit{StorageUnit\_charge\_carried\_in}\) | StorageUnit_charge_carried_in over \(\Xi \times \mathcal{T} \times \mathcal{S}\) — the charge a unit opens a snapshot with — at the first snapshot it stands in, its last such snapshot's less standing loss where it is cyclic and the given initial charge, which no standing loss has touched yet, where it is not; the previous snapshot's less standing loss otherwise. A unit built in a later period opens in that period, and a cyclic one that retires closes on its own last snapshot. Per period, the same holds with each investment period as the horizon |
| \(\mathit{Store\_energy\_carried\_in}\) | Store_energy_carried_in over \(\Xi \times \mathcal{T} \times \mathcal{V}\) — the energy a store opens a snapshot with — at the first snapshot it stands in, its last such snapshot's less standing loss where it is cyclic and the given initial energy, which no standing loss has touched yet, where it is not; the previous snapshot's less standing loss otherwise. A store built in a later period opens in that period, and a cyclic one that retires closes on its own last snapshot. Per period, the same holds with each investment period as the horizon |
| \(\mathit{Link\_output\_arrival}\) | Link_output_arrival over \(\Xi \times \mathcal{T} \times \mathcal{O}\) — what a link delivers to an output port at a snapshot — its flow delayed by the port's delay within its investment period, times the port's efficiency at the snapshot the flow arrives; where the port is cyclic_delay the delayed flow wraps from the period's end, and where it is not the flow still in transit at the period's first snapshots is lost. A port that does not delay (delay zero) delivers its flow unshifted, cyclic or not |
| \(\mathit{Process\_output\_arrival}\) | Process_output_arrival over \(\Xi \times \mathcal{T} \times \mathcal{R}\) — what a process transfers at a port at a snapshot — its internal power delayed by the port's delay within its investment period, times the port's rate at the snapshot the transfer arrives; where the port is cyclic_delay the delayed transfer wraps from the period's end, and where it is not the energy still in transit at the period's first snapshots is lost. A port that does not delay (delay zero) transfers at once, cyclic or not |
| \(\mathit{Generator\_opex}\) | Generator_opex over \(\Xi\) |
| \(\mathit{StorageUnit\_opex}\) | StorageUnit_opex over \(\Xi\) |
| \(\mathit{Store\_opex}\) | Store_opex over \(\Xi\) |
| \(\mathit{scenario\_opex}\) | scenario_opex over \(\Xi\) — what a future costs to run — every operating term, weighted by the snapshot's hours and its period, before the scenario's own weight; a start and a stop cost what they cost, unweighted, as PyPSA adds them (optimize.py:415-432) |
| \(\mathit{StorageUnit\_capex}\) | StorageUnit_capex (scalar) |
| \(\mathit{Store\_capex}\) | Store_capex (scalar) |
| \(\mathit{risk\_weighted\_opex}\) | risk_weighted_opex (scalar) |
| \(\mathit{total\_cost}\) | total_cost (scalar) — what the system costs — capacity once per active period at its expected cost over the scenarios, operation in expectation over the scenarios, and a share of it at the tail |
| \(\mathit{StorageUnit\_additions}\) | StorageUnit_additions over \(\mathcal{I} \times \mathcal{Y}\) |
| \(\mathit{Store\_additions}\) | Store_additions over \(\mathcal{I} \times \mathcal{Y}\) |
| \(\mathit{Carrier\_additions}\) | Carrier_additions over \(\mathcal{Y} \times \mathcal{I}\) — what a carrier adds in a period — every extendable component of that carrier, counting each build in the first period it stands in. Like PyPSA, it sums only the components that carry a carrier attribute, so a transformer, which has none, counts in no carrier |
| \(\mathrm{Carrier\_relative\_growth}\) | Carrier_relative_growth over \(\mathcal{I}\) — the share of the previous period's additions a carrier's growth limit reads — PyPSA's max_relative_growth clipped at zero, so a negative share adds nothing and never tightens the limit |
| \(\mathrm{Load\_demand}\) | Load_demand over \(\Xi \times \mathcal{T} \times \mathcal{D}\) — what a load draws from its bus's balance — its demand times its sign where it is active, nothing where it is not, since PyPSA drops an inactive load from the balance (constraints.py:1513-1514) |
| \(\mathit{Generator\_injection}\) | Generator_injection over \(\mathcal{N} \times \Xi \times \mathcal{T}\) |
| \(\mathit{Link\_injection}\) | Link_injection over \(\mathcal{N} \times \Xi \times \mathcal{T}\) |
| \(\mathrm{Load\_injection}\) | Load_injection over \(\mathcal{N} \times \Xi \times \mathcal{T}\) |
| \(\mathit{Process\_injection}\) | Process_injection over \(\mathcal{N} \times \Xi \times \mathcal{T}\) |
| \(\mathit{StorageUnit\_injection}\) | StorageUnit_injection over \(\mathcal{N} \times \Xi \times \mathcal{T}\) |
| \(\mathit{Store\_injection}\) | Store_injection over \(\mathcal{N} \times \Xi \times \mathcal{T}\) |
| \(\mathit{Bus\_injection}\) | Bus_injection over \(\Xi \times \mathcal{T} \times \mathcal{N}\) — what every component puts into a bus, less what it takes out of it; PyPSA writes each term into the balance, and a load on its right-hand side |
Notation¶
| Symbol | Meaning |
|---|---|
| \(t \ominus k\) | edge='wrap' — \(t-k\), cyclic |
| \(t \boxminus_{v} k\) | edge=v — \(t-k\), and \(v\) past the edge |
| \(t \ominus^{\mathrm{relation}(t)} k\) | within=relation[...] — \(t-k\) inside the group of \(t\) |
| \(\mathrm{pos}(t)\) | position() — the position of \(t\), counted from \(0\); \(t\) is the label |
| \(\mathrm{pos}_{\mathrm{relation}(t)}(t)\) | position(within=relation[...]) — the position of \(t\) inside its group |
Conditions¶
StorageUnit_ext
Variable domains¶
Generator_p
StorageUnit_p_dispatch
StorageUnit_p_store
StorageUnit_state_of_charge
Store_e
Store_p
StorageUnit_p_nom_ext
Store_e_nom_ext
Link_p
Process_p
Definitions¶
StorageUnit_charge_carried_in
Store_energy_carried_in
Link_output_arrival
Process_output_arrival
Generator_opex
StorageUnit_opex
Store_opex
scenario_opex
StorageUnit_capex
Store_capex
risk_weighted_opex
total_cost
StorageUnit_additions
Store_additions
Carrier_additions
Carrier_relative_growth
Load_demand
Generator_injection
Link_injection
Load_injection
Process_injection
StorageUnit_injection
Store_injection
Bus_injection
Objective¶
Subject to¶
Generator_fix_p_lower
Generator_fix_p_upper
StorageUnit_ext_p_dispatch_lower
StorageUnit_ext_p_dispatch_upper
StorageUnit_ext_p_store_lower
StorageUnit_ext_p_store_upper
StorageUnit_ext_state_of_charge_lower
StorageUnit_ext_state_of_charge_upper
StorageUnit_ext_p_nom_lower
StorageUnit_ext_p_nom_upper
StorageUnit_energy_balance
Store_ext_e_lower
Store_ext_e_upper
Store_ext_e_nom_lower
Store_ext_e_nom_upper
Store_energy_balance
Bus_nodal_balance
Carrier_growth_limit
The spec, differential/pypsa/rungs/rung_21_carrier_growth.yaml — the file projected onto what this rung builds:
description: A plain `n.optimize()`, and its multi-period and stochastic classes, in one file. Every second-stage
quantity spans a `scenario` (a future dispatch is chosen in) and every asset stands in the investment
`period`s its build year and lifetime span. A parameter spans `scenario` exactly when PyPSA reads it
per scenario. Capacity is chosen once, before the future is known, and paid once per active period at
its cost in expectation over the scenarios; operation is the expectation over the scenarios' weights,
with a share priced at the tail through the CVaR rows, which stand only where a risk preference is set.
A plain run feeds one scenario, one period, all-active masks and unit weights, and the model collapses
to the standard one. A security-constrained run copies each branch flow limit once per outage in an
`outage` set that a plain run leaves empty. Which snapshots an asset is active in, a scenario's weight,
and the outage factors are data prep.
dimensions:
scenario: {description: 'the futures dispatch is chosen in, each with a weight'}
snapshot: {description: dispatch periods, dtype: datetime, ordered: true}
bus: {description: network nodes}
generator: {description: 'generating units, each on one bus'}
link: {description: 'controllable connections, each from one bus to the buses it delivers to'}
link_output: {description: 'a link''s output ports, one label per port a link declares — PyPSA''s `bus1`,
`bus2`, … columns read long, so a link of any number of output ports is one term in the balance,
data prep'}
process: {description: 'generalized multi-port converters, each with an internal power that every port
draws or delivers at its own rate'}
process_output: {description: 'a process''s ports, one label per port a process declares — PyPSA''s
`bus0`, `bus1`, … each carry a signed `rate`, so a process of any number of ports is one term in
the balance, data prep'}
load: {description: 'demands, each on one bus'}
storage_unit: {description: 'storage units, dispatch and store behind one bus connection'}
store: {description: 'pure energy stores, each on one bus'}
period: {description: investment periods — PyPSA's `investment_periods`, dtype: int, ordered: true}
carrier: {description: 'energy carriers, what a growth limit is set per'}
relations:
snapshot_period: {description: the investment period a snapshot falls in, key: snapshot, values: period}
Generator_bus: {description: the bus a generator sits on, key: generator, values: bus}
Link_output_link: {description: the link an output port belongs to, key: link_output, values: link}
Link_output_bus: {description: 'the bus an output port delivers to — PyPSA''s `bus1`, `bus2`, … columns.
A link of three output ports is three labels here rather than a third relation, so the file states
any number of them', key: link_output, values: bus}
Process_output_process: {description: the process a port belongs to, key: process_output, values: process}
Process_output_bus: {description: 'the bus a port draws from or delivers to — PyPSA''s `bus0`, `bus1`,
… columns. A process of three ports is three labels here rather than a third relation, so the file
states any number of them', key: process_output, values: bus}
Load_bus: {description: the bus a load sits on, key: load, values: bus}
StorageUnit_carrier: {description: the carrier a storage unit converts from, key: storage_unit, values: carrier}
StorageUnit_bus: {description: the bus a storage unit sits on, key: storage_unit, values: bus}
Store_carrier: {description: the carrier a store holds, key: store, values: carrier}
Store_bus: {description: the bus a store sits on, key: store, values: bus}
parameters:
snapshot_weightings_objective:
description: PyPSA's `snapshot_weightings.objective` — hours a snapshot stands for in the cost
dims: [snapshot]
Generator_p_nom:
description: nominal power
dims: [scenario, generator]
Generator_p_nom_extendable:
description: whether the nominal power is a decision
dims: [generator]
dtype: bool
Generator_p_min_pu:
description: least output, per unit of nominal power
dims: [scenario, snapshot, generator]
Generator_p_max_pu:
description: most output, per unit of nominal power — an availability profile
dims: [scenario, snapshot, generator]
Generator_marginal_cost:
description: cost of one unit of output
dims: [scenario, snapshot, generator]
Generator_marginal_cost_quadratic:
description: cost of the square of one unit of output
dims: [scenario, snapshot, generator]
Generator_sign:
description: the sign output enters its bus's balance with — PyPSA's `sign`, `1` unless given, `-1`
for a unit that draws power. PyPSA refuses one that differs by scenario (`constants.py:43`)
dims: [generator]
Generator_committable:
description: whether output is gated by an on/off status decision
dims: [generator]
dtype: bool
Link_efficiency:
description: share of the flow that arrives at an output port, PyPSA's `efficiency`, `efficiency2`,
… read long — negative where that port consumes rather than delivers. Read at the snapshot the flow
arrives, so a delayed port delivers at its arrival snapshot's efficiency (`constraints.py:1498`)
dims: [scenario, snapshot, link_output]
Link_output_delay:
description: snapshots a port's delivery lags its link's flow — PyPSA's `delay`, `delay2`, … read
long, divided by the `snapshot_weightings.generators` value and rounded up in data prep; zero for
a port that delivers at once. A port has the same delay in every scenario, because PyPSA refuses
a delay that differs by scenario (`constants.py:52`)
dims: [link_output]
dtype: int
Link_output_cyclic_delay:
description: whether a delayed port's flow wraps from the end of its investment period — PyPSA's `cyclic_delay`,
`cyclic_delay2`, …; where it does not, the flow still in transit at each period's first snapshots
is lost. The flag is the same in every scenario, as the delay is
dims: [link_output]
dtype: bool
Process_rate:
description: the energy a port draws or delivers per unit of internal power, PyPSA's `rate0`, `rate1`,
… read long — negative where the port withdraws, positive where it injects; a link is a process
whose `bus0` rate is minus one and whose output rates are its efficiencies. Read at the snapshot
the transfer arrives, so a delayed port transfers at its arrival snapshot's rate (`constraints.py:1498`)
dims: [scenario, snapshot, process_output]
Process_output_delay:
description: snapshots a port's transfer lags its process's internal power — PyPSA's `delay0`, `delay1`,
… read long, divided by the `snapshot_weightings.generators` value and rounded up in data prep;
zero for a port that transfers at once. A port has the same delay in every scenario, as a link's
port has
dims: [process_output]
dtype: int
Process_output_cyclic_delay:
description: whether a delayed port's transfer wraps from the end of its investment period — PyPSA's
`cyclic_delay0`, `cyclic_delay1`, …; where it does not, the energy still in transit at each period's
first snapshots is lost. The flag is the same in every scenario, as the delay is
dims: [process_output]
dtype: bool
Load_p_set:
description: demand
dims: [scenario, snapshot, load]
Load_sign:
description: the sign a load's demand enters its bus's balance with — PyPSA's `sign`, `-1` unless
given, `1` for a load that feeds its bus. PyPSA refuses one that differs by scenario (`constants.py:43`)
dims: [load]
Load_active:
description: whether a load stands in the model — PyPSA's `active`. A load has no build year and no
lifetime, so the flag holds in every snapshot. PyPSA refuses one that differs by scenario (`constants.py:51`)
dims: [load]
dtype: bool
scenario_weight:
description: PyPSA's `scenario_weightings.weight` — the probability of a future
dims: [scenario]
period_weight_objective:
description: PyPSA's `investment_period_weightings.objective` — what a period's cost weighs; PyPSA
reads it only under `multi_investment_periods`, so data prep feeds one otherwise, whatever the column
holds (`optimize.py:205-207`, `:264-266`)
dims: [period]
Generator_active:
description: whether a generator stands in a snapshot's period — PyPSA's `active`, from build year
and lifetime, data prep
dims: [snapshot, generator]
dtype: bool
Link_active:
description: whether a link stands in a snapshot's period — PyPSA's `active`, data prep
dims: [snapshot, link]
dtype: bool
StorageUnit_active:
description: whether a storage unit stands in a snapshot's period — PyPSA's `active`, data prep
dims: [snapshot, storage_unit]
dtype: bool
Store_active:
description: whether a store stands in a snapshot's period — PyPSA's `active`, data prep
dims: [snapshot, store]
dtype: bool
Process_active:
description: whether a process stands in a snapshot's period — PyPSA's `active`, data prep
dims: [snapshot, process]
dtype: bool
StorageUnit_active_asset:
description: whether a storage unit is one of PyPSA's `active_assets` — its `active` flag alone, without
build year and lifetime, so a unit that stands in no snapshot of the horizon still counts. PyPSA
refuses one that differs by scenario (`constants.py:51`)
dims: [storage_unit]
dtype: bool
Store_active_asset:
description: whether a store is one of PyPSA's `active_assets` — its `active` flag alone, without
build year and lifetime, so a unit that stands in no snapshot of the horizon still counts. PyPSA
refuses one that differs by scenario (`constants.py:51`)
dims: [store]
dtype: bool
StorageUnit_capital_weight:
description: the sum of period weights a storage unit stands in — PyPSA's `active * period_weighting`,
summed, data prep
dims: [storage_unit]
Store_capital_weight:
description: the sum of period weights a store stands in — PyPSA's `active * period_weighting`, summed,
data prep
dims: [store]
StorageUnit_first_active:
description: one in the first period a storage unit stands in, zero elsewhere, data prep. PyPSA takes
`active & (active.cumsum() == 1)` (`global_constraints.py:265`)
dims: [period, storage_unit]
Store_first_active:
description: one in the first period a store stands in, zero elsewhere, data prep. PyPSA takes `active
& (active.cumsum() == 1)` (`global_constraints.py:265`)
dims: [period, store]
Carrier_max_growth:
description: most capacity of a carrier that may be added in a period; no value means no limit. The
least over the scenarios, as PyPSA takes it (`global_constraints.py:227-231`), data prep. PyPSA
reads it only under `multi_investment_periods` (`global_constraints.py:220-221`), so data prep feeds
no value otherwise
dims: [carrier]
missing: neutral
Carrier_max_relative_growth:
description: share of the previous period's additions that may be added on top — the least over the
scenarios, as PyPSA takes it, data prep
dims: [carrier]
snapshot_weightings_stores:
description: PyPSA's `snapshot_weightings.stores` — hours a snapshot stands for in a storage balance
dims: [snapshot]
StorageUnit_p_nom_min:
description: least nominal power an extendable storage unit may be built at
dims: [scenario, storage_unit]
StorageUnit_p_nom_max:
description: most nominal power an extendable storage unit may be built at
dims: [scenario, storage_unit]
StorageUnit_capital_cost:
description: 'cost of one unit of nominal power for the modelled horizon — PyPSA''s `periodized_cost`:
`overnight_cost` as an annuity over `lifetime` at `discount_rate`, times `nyears`, where it is given,
and `capital_cost` where it is not, plus `fom_cost` (`components.py:1126-1147`, `costs.py:102-203`),
data prep'
dims: [scenario, storage_unit]
Store_e_nom_min:
description: least nominal capacity an extendable store may be built at
dims: [scenario, store]
Store_e_nom_max:
description: most nominal capacity an extendable store may be built at
dims: [scenario, store]
Store_capital_cost:
description: 'cost of one unit of nominal capacity for the modelled horizon — PyPSA''s `periodized_cost`:
`overnight_cost` as an annuity over `lifetime` at `discount_rate`, times `nyears`, where it is given,
and `capital_cost` where it is not, plus `fom_cost` (`components.py:1126-1147`, `costs.py:102-203`),
data prep'
dims: [scenario, store]
StorageUnit_p_nom_extendable:
description: whether the nominal power is a decision
dims: [storage_unit]
dtype: bool
StorageUnit_p_min_pu:
description: most storing, per unit of nominal power and negated
dims: [scenario, snapshot, storage_unit]
StorageUnit_p_max_pu:
description: most dispatch, per unit of nominal power
dims: [scenario, snapshot, storage_unit]
StorageUnit_max_hours:
description: energy capacity, as hours of dispatch at nominal power
dims: [scenario, storage_unit]
StorageUnit_efficiency_store:
description: share of the power drawn from the bus that becomes charge
dims: [scenario, snapshot, storage_unit]
StorageUnit_efficiency_dispatch:
description: share of the charge drawn down that reaches the bus
dims: [scenario, snapshot, storage_unit]
StorageUnit_sign:
description: the sign net dispatch enters its bus's balance with — PyPSA's `sign`, `1` unless given.
PyPSA refuses one that differs by scenario (`constants.py:43`)
dims: [storage_unit]
StorageUnit_retention:
description: share of charge kept over a snapshot — PyPSA's `(1 - standing_loss) ** elapsed hours`,
data prep
dims: [scenario, snapshot, storage_unit]
StorageUnit_inflow:
description: energy arriving per hour, a river into a reservoir
dims: [scenario, snapshot, storage_unit]
StorageUnit_state_of_charge_initial:
description: charge held before the first snapshot
dims: [scenario, storage_unit]
StorageUnit_cyclic_state_of_charge:
description: whether the horizon closes on itself instead of opening on the initial charge
dims: [scenario, storage_unit]
dtype: bool
StorageUnit_cyclic_state_of_charge_per_period:
description: whether each investment period closes on itself instead of carrying its charge on to
the next; it overrides `cyclic_state_of_charge` and `state_of_charge_initial_per_period`. PyPSA
reads it only under `multi_investment_periods`, so data prep feeds false otherwise
dims: [scenario, storage_unit]
dtype: bool
StorageUnit_state_of_charge_initial_per_period:
description: whether each investment period opens on the initial charge instead of carrying the previous
period's; PyPSA reads it only under `multi_investment_periods`, so data prep feeds false otherwise
dims: [scenario, storage_unit]
dtype: bool
StorageUnit_opens_late:
description: whether a snapshot is the first a storage unit stands in, where that is not the first
of the horizon — PyPSA's `active.cumsum() == 1` over the snapshots it stands in, past the first
snapshot, data prep; false in a run where every unit stands throughout
dims: [snapshot, storage_unit]
dtype: bool
StorageUnit_inactive_snapshots:
description: how many snapshots a storage unit does not stand in — PyPSA's `(~active).sum()`, data
prep. A cyclic unit reaches back this many snapshots further, so it closes on the last snapshot
it stands in
dims: [storage_unit]
dtype: int
StorageUnit_marginal_cost:
description: cost of one unit of dispatch
dims: [scenario, snapshot, storage_unit]
StorageUnit_marginal_cost_quadratic:
description: cost of the square of one unit of dispatch; storing is not charged
dims: [scenario, snapshot, storage_unit]
StorageUnit_marginal_cost_storage:
description: cost of one unit of charge held over one snapshot
dims: [scenario, snapshot, storage_unit]
Store_e_nom_extendable:
description: whether the nominal energy capacity is a decision
dims: [store]
dtype: bool
Store_e_min_pu:
description: least energy held, per unit of nominal capacity — negative for a store that may go short
dims: [scenario, snapshot, store]
Store_e_max_pu:
description: most energy held, per unit of nominal capacity
dims: [scenario, snapshot, store]
Store_sign:
description: the sign the power a store delivers enters its bus's balance with — PyPSA's `sign`, `1`
unless given. PyPSA refuses one that differs by scenario (`constants.py:43`)
dims: [store]
Store_retention:
description: share of energy kept over a snapshot — PyPSA's `(1 - standing_loss) ** elapsed hours`,
data prep
dims: [scenario, snapshot, store]
Store_e_initial:
description: energy held before the first snapshot
dims: [scenario, store]
Store_e_cyclic:
description: whether the horizon closes on itself instead of opening on the initial energy
dims: [scenario, store]
dtype: bool
Store_e_cyclic_per_period:
description: whether each investment period closes on itself instead of carrying its energy on to
the next; it overrides `e_cyclic` and `e_initial_per_period`. PyPSA reads it only under `multi_investment_periods`,
so data prep feeds false otherwise
dims: [scenario, store]
dtype: bool
Store_e_initial_per_period:
description: whether each investment period opens on the initial energy instead of carrying the previous
period's; PyPSA reads it only under `multi_investment_periods`, so data prep feeds false otherwise
dims: [scenario, store]
dtype: bool
Store_opens_late:
description: whether a snapshot is the first a store stands in, where that is not the first of the
horizon — PyPSA's `active.cumsum() == 1` over the snapshots it stands in, past the first snapshot,
data prep; false in a run where every store stands throughout
dims: [snapshot, store]
dtype: bool
Store_inactive_snapshots:
description: how many snapshots a store does not stand in — PyPSA's `(~active).sum()`, data prep.
A cyclic store reaches back this many snapshots further, so it closes on the last snapshot it stands
in
dims: [store]
dtype: int
Store_marginal_cost:
description: cost of one unit of power delivered
dims: [scenario, snapshot, store]
Store_marginal_cost_quadratic:
description: cost of the square of the net power delivered, so charging costs as much as delivering
dims: [scenario, snapshot, store]
Store_marginal_cost_storage:
description: cost of one unit of energy held over one snapshot
dims: [scenario, snapshot, store]
variables:
Generator_p:
description: '`Generator-p` — output of a generator in a snapshot'
dims: [scenario, snapshot, generator]
where: Generator_active
StorageUnit_p_dispatch:
description: '`StorageUnit-p_dispatch` — power delivered to the bus'
dims: [scenario, snapshot, storage_unit]
where: StorageUnit_active
StorageUnit_p_store:
description: '`StorageUnit-p_store` — power drawn from the bus into charge'
dims: [scenario, snapshot, storage_unit]
where: StorageUnit_active
StorageUnit_state_of_charge:
description: '`StorageUnit-state_of_charge` — energy held at the end of a snapshot'
dims: [scenario, snapshot, storage_unit]
where: StorageUnit_active
Store_e:
description: '`Store-e` — energy held at the end of a snapshot'
dims: [scenario, snapshot, store]
where: Store_active
Store_p:
description: '`Store-p` — power delivered to the bus; charging is negative'
dims: [scenario, snapshot, store]
where: Store_active
StorageUnit_p_nom_ext:
description: '`StorageUnit-p_nom` — nominal power where it is a decision, for a storage unit that
is active; the parameter of the same PyPSA name carries the fixed regime'
dims: [storage_unit]
where: StorageUnit_p_nom_extendable AND StorageUnit_active_asset
Store_e_nom_ext:
description: '`Store-e_nom` — nominal capacity where it is a decision, for a store that is active;
the parameter of the same PyPSA name carries the fixed regime'
dims: [store]
where: Store_e_nom_extendable AND Store_active_asset
Link_p:
description: '`Link-p` — PyPSA''s `p0`, the flow measured at the `Link_bus0` end: a positive value
withdraws there and injects at every bus the link''s output ports deliver to'
dims: [scenario, snapshot, link]
where: Link_active
Process_p:
description: '`Process-p` — PyPSA''s internal power `p`: a positive value drives every port at its
own rate, withdrawing where the rate is negative and injecting where it is positive'
dims: [scenario, snapshot, process]
where: Process_active
constraints:
Generator_fix_p_lower:
description: '`Generator-fix-p-lower` — a fixed generator outputs at least its minimum'
dims: [scenario, snapshot, generator]
where: not Generator_p_nom_extendable AND not Generator_committable AND Generator_active
expression: Generator_p >= Generator_p_min_pu * Generator_p_nom
Generator_fix_p_upper:
description: '`Generator-fix-p-upper` — a fixed generator outputs at most what is available'
dims: [scenario, snapshot, generator]
where: not Generator_p_nom_extendable AND not Generator_committable AND Generator_active
expression: Generator_p <= Generator_p_max_pu * Generator_p_nom
StorageUnit_ext_p_dispatch_lower:
description: '`StorageUnit-ext-p_dispatch-lower` — dispatch is non-negative'
dims: [scenario, snapshot, storage_unit]
where: StorageUnit_ext
expression: StorageUnit_p_dispatch >= 0
StorageUnit_ext_p_dispatch_upper:
description: '`StorageUnit-ext-p_dispatch-upper` — an extendable unit dispatches at most the chosen
build'
dims: [scenario, snapshot, storage_unit]
where: StorageUnit_ext
expression: StorageUnit_p_dispatch <= StorageUnit_p_max_pu * StorageUnit_p_nom_ext
StorageUnit_ext_p_store_lower:
description: '`StorageUnit-ext-p_store-lower` — storing is non-negative'
dims: [scenario, snapshot, storage_unit]
where: StorageUnit_ext
expression: StorageUnit_p_store >= 0
StorageUnit_ext_p_store_upper:
description: '`StorageUnit-ext-p_store-upper` — an extendable unit stores at most the chosen build,
the minimum-per-unit column carrying that cap negated'
dims: [scenario, snapshot, storage_unit]
where: StorageUnit_ext
expression: StorageUnit_p_store <= -StorageUnit_p_min_pu * StorageUnit_p_nom_ext
StorageUnit_ext_state_of_charge_lower:
description: '`StorageUnit-ext-state_of_charge-lower` — charge is non-negative'
dims: [scenario, snapshot, storage_unit]
where: StorageUnit_ext
expression: StorageUnit_state_of_charge >= 0
StorageUnit_ext_state_of_charge_upper:
description: '`StorageUnit-ext-state_of_charge-upper` — an extendable unit holds at most its hours
at the chosen build'
dims: [scenario, snapshot, storage_unit]
where: StorageUnit_ext
expression: StorageUnit_state_of_charge <= StorageUnit_max_hours * StorageUnit_p_nom_ext
StorageUnit_ext_p_nom_lower:
description: '`StorageUnit-ext-p_nom-lower` — the chosen build is at least its floor in every scenario'
dims: [scenario, storage_unit]
where: StorageUnit_p_nom_extendable AND StorageUnit_active_asset
expression: StorageUnit_p_nom_ext >= StorageUnit_p_nom_min
StorageUnit_ext_p_nom_upper:
description: '`StorageUnit-ext-p_nom-upper` — the chosen build is at most its cap in every scenario;
a cap of infinity is no row'
dims: [scenario, storage_unit]
where: StorageUnit_p_nom_extendable AND StorageUnit_active_asset AND StorageUnit_p_nom_max
expression: StorageUnit_p_nom_ext <= StorageUnit_p_nom_max
StorageUnit_energy_balance:
description: '`StorageUnit-energy_balance` — the charge carried in, plus what is stored after its
efficiency, less what dispatch draws down before its own, plus inflow not spilled'
dims: [scenario, snapshot, storage_unit]
where: StorageUnit_active
expression: StorageUnit_state_of_charge == ((StorageUnit_charge_carried_in + ((StorageUnit_efficiency_store
* StorageUnit_p_store) * snapshot_weightings_stores)) - ((StorageUnit_p_dispatch * snapshot_weightings_stores)
/ StorageUnit_efficiency_dispatch)) + (StorageUnit_inflow * snapshot_weightings_stores)
Store_ext_e_lower:
description: '`Store-ext-e-lower` — an extendable store holds at least its floor of the chosen build'
dims: [scenario, snapshot, store]
where: Store_e_nom_extendable AND Store_active
expression: Store_e >= Store_e_min_pu * Store_e_nom_ext
Store_ext_e_upper:
description: '`Store-ext-e-upper` — an extendable store holds at most the chosen build'
dims: [scenario, snapshot, store]
where: Store_e_nom_extendable AND Store_active
expression: Store_e <= Store_e_max_pu * Store_e_nom_ext
Store_ext_e_nom_lower:
description: '`Store-ext-e_nom-lower` — the chosen build is at least its floor in every scenario'
dims: [scenario, store]
where: Store_e_nom_extendable AND Store_active_asset
expression: Store_e_nom_ext >= Store_e_nom_min
Store_ext_e_nom_upper:
description: '`Store-ext-e_nom-upper` — the chosen build is at most its cap in every scenario; a cap
of infinity is no row'
dims: [scenario, store]
where: Store_e_nom_extendable AND Store_active_asset AND Store_e_nom_max
expression: Store_e_nom_ext <= Store_e_nom_max
Store_energy_balance:
description: '`Store-energy_balance` — the energy carried in, less what is delivered to the bus'
dims: [scenario, snapshot, store]
where: Store_active
expression: Store_e == Store_energy_carried_in - Store_p * snapshot_weightings_stores
Bus_nodal_balance:
description: '`Bus-nodal_balance` — what is generated at a bus, storage dispatch and stores included,
less what the links take away, plus what arrives over them after losses and any delay at every port
they deliver to, each process port drawing or delivering at its own rate and each passive branch
carrying its flow, meets the load there, less half of every incident line''s and transformer''s
loss — PyPSA dissipates a branch''s loss half at either end. Each generator, storage unit, store
and load term enters with its component''s `sign` (`constraints.py:1404-1405`, `:1514`), and an
inactive load not at all. A bus nothing is attached to has no row; PyPSA refuses one that carries
load, and this file does not yet.'
dims: [scenario, snapshot, bus]
expression: Bus_injection == 0
Carrier_growth_limit:
description: '`Carrier-growth_limit` — what a carrier adds across its extendable components in a period,
counting each build in the first period it stands in, is at most its allowance plus a share of what
it added the period before; the first period has no predecessor, so `edge=0` leaves it the bare
allowance'
dims: [carrier, period]
where: Carrier_max_growth
expression: Carrier_additions - shift(Carrier_additions, along=period, offset=1, edge=0) * Carrier_relative_growth
<= Carrier_max_growth
expressions:
StorageUnit_charge_carried_in:
description: the charge a unit opens a snapshot with — at the first snapshot it stands in, its last
such snapshot's less standing loss where it is cyclic and the given initial charge, which no standing
loss has touched yet, where it is not; the previous snapshot's less standing loss otherwise. A unit
built in a later period opens in that period, and a cyclic one that retires closes on its own last
snapshot. Per period, the same holds with each investment period as the horizon
dims: [scenario, snapshot, storage_unit]
cases:
cyclic: {when: StorageUnit_cyclic_state_of_charge AND NOT StorageUnit_cyclic_state_of_charge_per_period
AND NOT StorageUnit_state_of_charge_initial_per_period AND (position(snapshot) == 0 OR StorageUnit_opens_late),
expression: 'StorageUnit_retention * shift(shift(StorageUnit_state_of_charge, along=snapshot,
offset=1, edge=''wrap''), along=snapshot, offset=StorageUnit_inactive_snapshots, edge=''wrap'')'}
opening: {when: NOT StorageUnit_cyclic_state_of_charge AND NOT StorageUnit_cyclic_state_of_charge_per_period
AND NOT StorageUnit_state_of_charge_initial_per_period AND (position(snapshot) == 0 OR StorageUnit_opens_late),
expression: StorageUnit_state_of_charge_initial}
period_cyclic: {when: StorageUnit_cyclic_state_of_charge_per_period, expression: 'StorageUnit_retention
* shift(StorageUnit_state_of_charge, along=snapshot, offset=1, edge=''wrap'', within=snapshot_period[period])'}
period_opening: {when: 'StorageUnit_state_of_charge_initial_per_period AND NOT StorageUnit_cyclic_state_of_charge_per_period
AND position(snapshot, within=snapshot_period[period]) == 0', expression: StorageUnit_state_of_charge_initial}
otherwise: StorageUnit_retention * shift(StorageUnit_state_of_charge, along=snapshot, offset=1)
Store_energy_carried_in:
description: the energy a store opens a snapshot with — at the first snapshot it stands in, its last
such snapshot's less standing loss where it is cyclic and the given initial energy, which no standing
loss has touched yet, where it is not; the previous snapshot's less standing loss otherwise. A store
built in a later period opens in that period, and a cyclic one that retires closes on its own last
snapshot. Per period, the same holds with each investment period as the horizon
dims: [scenario, snapshot, store]
cases:
cyclic: {when: Store_e_cyclic AND NOT Store_e_cyclic_per_period AND NOT Store_e_initial_per_period
AND (position(snapshot) == 0 OR Store_opens_late), expression: 'Store_retention * shift(shift(Store_e,
along=snapshot, offset=1, edge=''wrap''), along=snapshot, offset=Store_inactive_snapshots, edge=''wrap'')'}
opening: {when: NOT Store_e_cyclic AND NOT Store_e_cyclic_per_period AND NOT Store_e_initial_per_period
AND (position(snapshot) == 0 OR Store_opens_late), expression: Store_e_initial}
period_cyclic: {when: Store_e_cyclic_per_period, expression: 'Store_retention * shift(Store_e, along=snapshot,
offset=1, edge=''wrap'', within=snapshot_period[period])'}
period_opening: {when: 'Store_e_initial_per_period AND NOT Store_e_cyclic_per_period AND position(snapshot,
within=snapshot_period[period]) == 0', expression: Store_e_initial}
otherwise: Store_retention * shift(Store_e, along=snapshot, offset=1)
Link_output_arrival:
description: what a link delivers to an output port at a snapshot — its flow delayed by the port's
`delay` within its investment period, times the port's efficiency at the snapshot the flow arrives;
where the port is `cyclic_delay` the delayed flow wraps from the period's end, and where it is not
the flow still in transit at the period's first snapshots is lost. A port that does not delay (`delay`
zero) delivers its flow unshifted, cyclic or not
dims: [scenario, snapshot, link_output]
cases:
wrapping: {when: Link_output_cyclic_delay, expression: 'shift(at(Link_p, by=Link_output_link[link]),
along=snapshot, offset=Link_output_delay, edge=''wrap'', within=snapshot_period[period]) * Link_efficiency'}
otherwise: shift(at(Link_p, by=Link_output_link[link]), along=snapshot, offset=Link_output_delay,
edge=0, within=snapshot_period[period]) * Link_efficiency
Process_output_arrival:
description: what a process transfers at a port at a snapshot — its internal power delayed by the
port's `delay` within its investment period, times the port's rate at the snapshot the transfer
arrives; where the port is `cyclic_delay` the delayed transfer wraps from the period's end, and
where it is not the energy still in transit at the period's first snapshots is lost. A port that
does not delay (`delay` zero) transfers at once, cyclic or not
dims: [scenario, snapshot, process_output]
cases:
wrapping: {when: Process_output_cyclic_delay, expression: 'shift(at(Process_p, by=Process_output_process[process]),
along=snapshot, offset=Process_output_delay, edge=''wrap'', within=snapshot_period[period])
* Process_rate'}
otherwise: shift(at(Process_p, by=Process_output_process[process]), along=snapshot, offset=Process_output_delay,
edge=0, within=snapshot_period[period]) * Process_rate
Generator_opex: {expression: 'sum(sum(((Generator_p * Generator_marginal_cost) * snapshot_weightings_objective)
* at(period_weight_objective, by=snapshot_period[period]), over=generator), over=snapshot) + sum(sum((((Generator_p
* Generator_p) * Generator_marginal_cost_quadratic) * snapshot_weightings_objective) * at(period_weight_objective,
by=snapshot_period[period]), over=generator), over=snapshot)'}
StorageUnit_opex: {expression: '(sum(sum(((StorageUnit_p_dispatch * StorageUnit_marginal_cost) * snapshot_weightings_objective)
* at(period_weight_objective, by=snapshot_period[period]), over=storage_unit), over=snapshot) +
sum(sum((((StorageUnit_p_dispatch * StorageUnit_p_dispatch) * StorageUnit_marginal_cost_quadratic)
* snapshot_weightings_objective) * at(period_weight_objective, by=snapshot_period[period]), over=storage_unit),
over=snapshot)) + sum(sum(((StorageUnit_state_of_charge * StorageUnit_marginal_cost_storage) * snapshot_weightings_objective)
* at(period_weight_objective, by=snapshot_period[period]), over=storage_unit), over=snapshot)'}
Store_opex: {expression: 'sum(sum(((Store_p * Store_marginal_cost) * snapshot_weightings_objective)
* at(period_weight_objective, by=snapshot_period[period]), over=store), over=snapshot) + sum(sum((((Store_p
* Store_p) * Store_marginal_cost_quadratic) * snapshot_weightings_objective) * at(period_weight_objective,
by=snapshot_period[period]), over=store), over=snapshot) + sum(sum(((Store_e * Store_marginal_cost_storage)
* snapshot_weightings_objective) * at(period_weight_objective, by=snapshot_period[period]), over=store),
over=snapshot)'}
scenario_opex:
dims: [scenario]
expression: (Generator_opex + StorageUnit_opex) + Store_opex
description: what a future costs to run — every operating term, weighted by the snapshot's hours and
its period, before the scenario's own weight; a start and a stop cost what they cost, unweighted,
as PyPSA adds them (`optimize.py:415-432`)
StorageUnit_capex: {expression: sum(scenario_weight * StorageUnit_p_nom_ext * StorageUnit_capital_cost
* StorageUnit_capital_weight)}
Store_capex: {expression: sum(scenario_weight * Store_e_nom_ext * Store_capital_cost * Store_capital_weight)}
risk_weighted_opex: {expression: 'sum(scenario_weight * scenario_opex, over=scenario)'}
total_cost:
dims: []
expression: (StorageUnit_capex + Store_capex) + risk_weighted_opex
description: what the system costs — capacity once per active period at its expected cost over the
scenarios, operation in expectation over the scenarios, and a share of it at the tail
StorageUnit_additions: {expression: 'sum(StorageUnit_p_nom_ext * StorageUnit_first_active, over=storage_unit,
by=StorageUnit_carrier[carrier])'}
Store_additions: {expression: 'sum(Store_e_nom_ext * Store_first_active, over=store, by=Store_carrier[carrier])'}
Carrier_additions:
dims: [period, carrier]
expression: StorageUnit_additions + Store_additions
description: what a carrier adds in a period — every extendable component of that carrier, counting
each build in the first period it stands in. Like PyPSA, it sums only the components that carry
a carrier attribute, so a transformer, which has none, counts in no carrier
Carrier_relative_growth:
description: the share of the previous period's additions a carrier's growth limit reads — PyPSA's
`max_relative_growth` clipped at zero, so a negative share adds nothing and never tightens the limit
dims: [carrier]
cases:
positive: {when: Carrier_max_relative_growth > 0, expression: Carrier_max_relative_growth}
otherwise: 0
Load_demand:
description: what a load draws from its bus's balance — its demand times its sign where it is active,
nothing where it is not, since PyPSA drops an inactive load from the balance (`constraints.py:1513-1514`)
dims: [scenario, snapshot, load]
cases:
active: {when: Load_active, expression: Load_sign * Load_p_set}
otherwise: 0
Generator_injection: {expression: 'sum(Generator_sign * Generator_p, over=generator, by=Generator_bus[bus])'}
Link_injection: {expression: 'sum(Link_output_arrival, over=link_output, by=Link_output_bus[bus])'}
Load_injection: {expression: 'sum(Load_demand, over=load, by=Load_bus[bus])'}
Process_injection: {expression: 'sum(Process_output_arrival, over=process_output, by=Process_output_bus[bus])'}
StorageUnit_injection: {expression: 'sum(StorageUnit_sign * (StorageUnit_p_dispatch - StorageUnit_p_store),
over=storage_unit, by=StorageUnit_bus[bus])'}
Store_injection: {expression: 'sum(Store_sign * Store_p, over=store, by=Store_bus[bus])'}
Bus_injection:
dims: [scenario, snapshot, bus]
expression: ((((Generator_injection + Link_injection) + Load_injection) + Process_injection) + StorageUnit_injection)
+ Store_injection
description: what every component puts into a bus, less what it takes out of it; PyPSA writes each
term into the balance, and a load on its right-hand side
conditions:
StorageUnit_ext: {description: a storage unit with an extendable build that stands in the snapshot's
period — PyPSA's `ext` rows, condition: StorageUnit_p_nom_extendable AND StorageUnit_active}
objective: {sense: minimize, expression: total_cost}
The prep — every table the spec declares, from the network — and the solve:
from differential.pypsa.prep import relation, static, varying, weighting
n = build() # the network from the PyPSA tab
sources = {
'snapshot': pl.Series('snapshot', list(timesteps(n)), dtype=pl.Datetime('us')),
'bus': pl.Series('bus', list(names(n.buses.index).astype(str)), dtype=pl.String),
**{
dim: pl.Series(dim, list(names(n.static(component).index).astype(str)), dtype=pl.String)
for component, dim in DIM.items()
},
**scenarios(n),
**periods(n, multi),
**carriers(n, multi),
'Generator_bus': relation(n, 'Generator', 'bus'),
'Load_bus': relation(n, 'Load', 'bus'),
'StorageUnit_bus': relation(n, 'StorageUnit', 'bus'),
'Store_bus': relation(n, 'Store', 'bus'),
'snapshot_weightings_objective': weighting(n, 'objective'),
'Generator_sign': per_component('Generator', first_scenario(n.generators['sign'])),
'Load_p_set': varying(n, 'Load', 'p_set'),
'Load_sign': per_component('Load', first_scenario(loads['sign'])),
'Load_active': per_component('Load', first_scenario(loads['active']), bool),
'snapshot_weightings_stores': weighting(n, 'stores'),
}
with sps.solve('differential/pypsa/rungs/rung_21_carrier_growth.yaml', sources) as solution:
solution.objective # 8452.5
The network, rung_21_carrier_growth.py in the corpus — the spine plus what this rung adds:
# SPDX-FileCopyrightText: mathspec Contributors
#
# SPDX-License-Identifier: MIT
"""Rung 21: a carrier's growth limit binds its non-generator builds — a storage unit and two stores over two periods."""
from __future__ import annotations
from datetime import datetime
import pandas as pd
OPTIMIZE = {'multi_investment_periods': True}
def build():
"""A whole network, not the spine: cheap solar only at the first snapshot of each period, so battery capacity pays off but its growth is capped."""
import pypsa
n = pypsa.Network()
n.snapshots = pd.MultiIndex.from_tuples(
[(2020, datetime(2020, 1, 1, t)) for t in range(2)] + [(2030, datetime(2030, 1, 1, t)) for t in range(2)]
)
n.investment_periods = [2020, 2030]
n.investment_period_weightings['objective'] = [1.0, 0.5]
n.investment_period_weightings['years'] = [10.0, 10.0]
n.snapshot_weightings['objective'] = [2.0, 1.5, 2.5, 2.0]
n.add('Bus', 'grid')
n.add('Carrier', 'solar')
n.add('Carrier', 'gas')
n.add('Carrier', 'battery', max_growth=20, max_relative_growth=0.5)
n.add('Generator', 'solar', bus='grid', carrier='solar', p_nom=100, marginal_cost=1, p_max_pu=[1, 0, 1, 0])
n.add('Generator', 'backup', bus='grid', carrier='gas', p_nom=200, marginal_cost=80)
n.add(
'StorageUnit',
'bat20',
bus='grid',
carrier='battery',
p_nom_extendable=True,
p_nom_max=100,
max_hours=4,
capital_cost=50,
build_year=2020,
lifetime=30,
)
n.add(
'Store',
'tank20',
bus='grid',
carrier='battery',
e_nom_extendable=True,
e_nom_max=10,
capital_cost=10,
build_year=2020,
lifetime=30,
)
n.add(
'Store',
'tank30',
bus='grid',
carrier='battery',
e_nom_extendable=True,
e_nom_max=100,
capital_cost=8,
build_year=2030,
lifetime=30,
)
n.add('Load', 'town', bus='grid', p_set=[40, 60, 40, 80])
return n
The data¶
The tables this rung is the first to declare (4), as the prep produced them:
StorageUnit_carrier.csv
StorageUnit_first_active.csv
Store_carrier.csv
Store_first_active.csv