How many kW of solar do I need? A 4-step calculation for Armenia
How to size a solar system from your electricity bill or monthly kWh: a simple formula, a worked example for a 35,000 AMD bill, and the mistakes to avoid.
Author: LA Solar Armenia engineering team · Last updated: · Read time 4 min
Short answer. In Armenia, 1 kW of solar produces roughly 1,400–1,600 kWh per year. Divide your annual consumption (kWh) by 1,500 and you get the approximate capacity you need. A home using 700 kWh per month needs a system of about 5.5–6 kW.
1. Find your monthly consumption
Your electricity bill shows consumption in kWh. If you only know the amount paid, divide it by the current tariff (roughly 45–50 AMD/kWh for households, as a guide). A 35,000 AMD monthly bill corresponds to about 700–780 kWh.
2. Calculate annual consumption
Multiply the monthly figure by 12. Use a full-year average rather than a single summer or winter month: under net metering, the summer surplus offsets the winter shortfall.
3. Divide by the annual yield
- 8,400 kWh / 1,500 kWh per kW ≈ 5.6 kW
- With 630 W panels that is 9 panels (≈ 5.7 kW) on about 24 m² of roof.
4. Add future consumption
An electric car, a heat pump or extra air conditioners add significant load. If you plan them in the next 2–3 years, include them now; expanding later is possible but more expensive.
Common mistakes
- Sizing by roof area. The roof limits what fits, but capacity is set by consumption.
- Choosing the biggest system. Under net metering, producing far more than you consume rarely pays back.
- Ignoring shade. A chimney, neighbouring building or tree can cut output by 10–30%.
The exact capacity is determined after an on-site survey and analysis of your real consumption. Use our calculator for a preliminary estimate or request a free calculation.