Yield usage metering

SunSolve Yield usage is metered in module years. One module year is the usage of simulating one simple module, at 1× fidelity, over one year of weather data. Your subscription includes an allowance of module years, and each simulation you run draws on it.

Usage formula

Yield usage ($U$) is calculated for each simulation as:

$$U=\mathrm{RoundUp}(M\times (C\times F+Y-1))$$

where:

• $M$ is the number of modules in the unit system
• $C$ is the complexity multiplier applied when complex modules are used
• $F$ is the fidelity multiplier
• $Y$ is the number of years, with $Y=\mathrm{RoundUp}(T\mathrm{/}8784)$ and $T$ the number of weather timesteps in the simulated date range

The optical solve for each module is performed once, so complexity and fidelity are counted once, on the first year. Each additional year only repeats the electrical time-stepping, so it adds a flat one module year per module.

Usage inputs

InputSymbolValuesModules, $M$, Number of modules in the unit system.

Complexity multiplier, $C$, $10$ for complex modules and $1$ for simple modules (for example a module loaded from a PAN file).

Fidelity multiplier, $F$, $0.5$ / $1$ / $2$ / $4$ / $8$ as set by the fidelity level.

Timesteps, $T$, Length of the simulated date range divided by the weather file timestep.Years, $Y$, $\mathrm{RoundUp}(T\mathrm{/}8784)$.

A module loaded from a SunSolve Power file is a complex module. A module loaded from a PAN file or datasheet is a simple module. See Module — Simple vs complex for how the two types differ.

The usage estimate in the yield calculator and the usage breakdown in your subscription transaction history list these same inputs, so you can check any usage against this formula.

Years and timestep cadence

A year is counted as $8784$ timesteps, which is one leap year (366 days) of hourly data. Using a leap year rather than $8760$ hours means that a full year of hourly data, leap year or not, always counts as a single year. Any part year is rounded up to a whole year.

$T$ counts timesteps, not hours. Weather data with a finer cadence therefore produces more years for the same date range:

Weather timestepTimesteps in 365 days, $T$Years, $Y$60 minutes, $8760$, $1$30 minutes, $17520$, $2$15 minutes, $35040$, $4$5 minutes, $105120$, $12$

Rounding

The final result is rounded up to a whole number of module years. Rounding is applied to each simulation, so a simulation never uses less than one module year.

Analyses

An analysis runs several simulations, shown by the simulations required counter. Each simulation is metered separately using the formula above. When every simulation shares the same inputs, the analysis uses the number of simulations required multiplied by $U$.

When the allowance runs out

A simulation will not start if your remaining module-year allowance is not enough to cover it. To run it, reduce its usage (for example by lowering the fidelity level, using a simple module or shortening the date range) or add module years to your subscription.

Each simulation in an analysis is checked against your remaining allowance separately. If the allowance runs out partway through an analysis, the simulations that have already run are still metered, and the remaining simulations will not start. Before running an analysis, check that your remaining allowance covers the full estimate shown in the yield calculator.

Worked examples

Simple module, one year of hourly weather

For a simple module simulation with $M=100$, $C=1$, $F=1$, and $T=8784$:

$$Y=\mathrm{RoundUp}(8784\mathrm{/}8784)=1$$ $$U=\mathrm{RoundUp}(100\times (1\times 1+1-1))=100$$

The simulation consumes $100$ module years.

Complex module, two years of hourly weather and higher fidelity

For a complex module simulation with $M=100$, $C=10$, $F=2$, and $T=17568$:

$$Y=\mathrm{RoundUp}(17568\mathrm{/}8784)=2$$ $$U=\mathrm{RoundUp}(100\times (10\times 2+2-1))=\mathrm{RoundUp}(100\times 21)=2100$$

The simulation consumes $2100$ module years.

Simple module, 15-minute weather data

For a simple module simulation with $M=100$, $C=1$, $F=1$, and one 365-day year of 15-minute data, $T=35040$:

$$Y=\mathrm{RoundUp}(35040\mathrm{/}8784)=4$$ $$U=\mathrm{RoundUp}(100\times (1\times 1+4-1))=400$$

The simulation consumes $400$ module years, four times the usage of the same simulation with hourly data.

Rounding at low fidelity

For a simple module simulation with $M=5$, $C=1$, $F=0.5$, and $T=8784$:

$$U=\mathrm{RoundUp}(5\times (1\times 0.5+1-1))=\mathrm{RoundUp}(2.5)=3$$

The simulation consumes $3$ module years.

Analysis

An analysis with $4$ simulations required, each matching the first example above, consumes $4\times 100=400$ module years.

See Yield simulation options for the fidelity settings that drive $F$, and Analysis options for the simulations an analysis runs.