Tools
Energy maths, without the engineering degree
Four calculators that answer the questions people actually ask: what does this appliance cost me, how many panels do I need, what do these units mean, and how much energy will a plant really deliver?
Appliance bill estimator
Utilities bill energy, not power. Multiply watts by hours to get watt-hours, then divide by 1,000.
Reference tariffs: Ethiopia ~$0.003, Nigeria ~$0.05–0.12, South Africa ~$0.15–0.20, Kenya ~$0.18–0.22 per kWh. Diesel self-generation runs $0.30–0.50.
Solar system sizer
Rough sizing for an off-grid or backup solar system, allowing 20% for inverter, wiring and dust losses.
Most of Africa sees 4.5–6.5 peak sun hours a day — among the best solar resources on earth.
Energy unit converter
Kilo, mega, giga, tera — each step is a thousand times bigger. Here is what your number looks like everywhere else.
- Wh1,000,000
- kWh1,000
- GWh0.001
- TWh0.000001
- Joule3,600,000,000
- Litre of diesel (≈10 kWh)100
Capacity factor & output
Nameplate capacity is the promise. Capacity factor tells you what a plant actually delivers over a year.