Energy project simulator
Preliminary assessment
Calculation versions: energy-finance@1.0.0 y wind@1.0.0. Irradiation and PV output: PVGIS © European Union. Wind: NASA POWER project (NASA Langley Research Center). Cartography: Natural Earth.
How to use it
- 1Choose solar PV or wind and mark the location on the map (or type the latitude and longitude).
- 2Enter the capacity and configuration. For solar PV you can let PVGIS calculate the optimal tilt and orientation.
- 3Query the resource (PVGIS for sun, NASA POWER for wind) or enter it by hand if you have your own study.
- 4Replace the example economic values with those from your budget, contract or bill, and check the sensitivity.
How it calculates
- Solar PV: monthly output from PVGIS (PVcalc) for 1 kWp with your losses, technology and angles, multiplied by the capacity (the PVGIS calculation is linear with capacity).
- Wind: wind at hub height v(h) = v(50 m) · (h/50)^α; Weibull distribution with shape k and scale c = v̄ / Γ(1 + 1/k); generic cubic power curve between cut-in and rated speed; density correction for altitude; energy = average power × hours × availability × (1 − losses).
- Output in year t = year 1 × (1 − degradation)^(t−1). Revenue = output × price, with annual escalation. OPEX = fixed per kW + variable per MWh, with escalation.
- NPV = Σ cash flows / (1 + rate)^t, with the investment in year 0. IRR: the rate that makes NPV equal to zero. Simple payback, undiscounted.
- LCOE = (investment + discounted OPEX) / discounted energy. Debt with constant payments; coverage = project cash flow / debt service.
- One-year P90 = mean − 1.2816 × year-to-year deviation from PVGIS (assumes a normal distribution).
Verifiable example
1,000 kWp in Albarracín (Teruel; 40.407 N, 1.444 W) at the optimal 35° tilt, facing south, with 14% losses and 2025 silicon modules: PVGIS 5.3 gives 1,583.5 kWh per kWp per year, i.e. 1,583.5 MWh in the first year. With the example values (€700/kW, €15/kW·year rising 2%, 0.5% degradation, €50/MWh, 25 years and 6%): investment of €700,000, first-year cash flow of €64,175.74, NPV of €36,050, IRR of 6.57%, payback in 11.6 years and LCOE of €48.14/MWh. In the simulator the NPV can vary by a few euros: it requests the data for 1 kWp and PVGIS rounds it to hundredths.
Limitations
- It's a preliminary assessment: it doesn't replace a resource study, a technical project or an installer's offer.
- It doesn't assess grid access and connection: we have no capacity data, and being near a line doesn't mean there is capacity.
- Wind uses a generic power curve and the monthly mean wind from a coarse-resolution reanalysis (about 50 km): real wind depends on terrain and obstacles.
- Pre-tax results, without subsidies, network charges or an hourly price profile.
- Solar output doesn't include nearby shading, trackers or batteries; it does include the terrain horizon PVGIS calculates.