The one-minute answer
Find two figures on your latest bill: the total amount due for the month (not including arrears from earlier months) and the units consumed, shown in kWh. Divide the amount by the units.
Example (illustration only): a bill of KSh 14,600 for 500 units works out at KSh 14,600 ÷ 500 = KSh 29.20 per unit. That is close to the KSh 29.19 our savings calculator uses as a default for households using more than 100 units a month.
That single figure, your all-in cost per unit, is what solar competes against. Every unit your panels produce and you use is a unit you no longer buy at that price.
What each line on the bill means
Kenya Power bills are made up of a base energy charge plus a set of pass-through charges that the Energy and Petroleum Regulatory Authority (EPRA) reviews every month. The names on your bill may be abbreviated, but they map to these:
- Energy charge. The base price per unit, set by your tariff band (see below). It is usually the largest single line, but it is well under the total you pay per unit.
- Fuel energy cost charge. Passes on what it costs to run thermal (diesel) power stations. It moves with fuel prices and with how much thermal power was needed that month, which is why it rises in dry spells when hydro output falls.
- Foreign exchange (forex) charge. Covers the effect of shilling movements on power purchase costs priced in dollars and other currencies.
- Inflation adjustment. A small per-unit charge that tracks inflation.
- WARMA levy. A charge collected for the Water Resources Authority on hydro generation.
- REP levy. The Rural Electrification Programme levy, charged as a percentage of the energy charge.
- EPRA levy. The regulator's own levy, a few cents per unit.
- VAT. 16% on the energy and pass-through charges.
Add them together and the real cost per unit is far higher than the energy charge alone. On the domestic high-consumption band the base energy charge is KSh 19.08 per unit, but once the pass-throughs and VAT are added we estimate the all-in figure at around KSh 29.19. [source]
Pass-through charges change monthly. In August 2026 alone EPRA's changes added KSh 4.70 to every unit. That is why your own bill, not a published rate, is the right number to use.
Why your unit price jumps after 100 units
Domestic customers are billed in bands based on how much they use in the month. The base energy charges are:
| Band | Monthly use | Energy charge |
|---|---|---|
| Domestic Lifeline | Up to 30 units | KSh 12.23 per unit |
| Domestic Ordinary | 30 to 100 units | KSh 16.45 per unit |
| Domestic High-Consumption | Over 100 units | KSh 19.08 per unit |
Energy charge only, before pass-through charges, levies and VAT. Source: EPRA / Kenya Power schedule of tariffs. Check your own bill for the current figures.
Most family homes and almost every business are well over 100 units a month, so they pay the highest base rate on top of the pass-throughs. That is also the group for whom solar pays back fastest.
Prepaid tokens
If you buy tokens, the same sum works. Look at the token SMS or receipt: it shows the amount paid and the units credited. Divide the amount by the units. Take an average across a month of purchases, because the first tokens of the month can be priced differently from later ones once you pass a band threshold.
What to do with the number
- Size a system. Your monthly units tell you how big a system you can actually use. Our sizing guide walks through it.
- Estimate your saving. Enter your bill and your cost per unit in the savings calculator. It shows your new monthly bill, your monthly saving and the payback period.
- Get it checked. Send a photo of your bill on WhatsApp and we will reply within 24 hours with a written estimate on your own numbers.
Common questions
How do I calculate my cost per unit of electricity in Kenya?
Divide the total amount on your Kenya Power bill for the month by the units (kWh) consumed. For prepaid tokens, divide the amount paid by the units credited. This all-in figure includes the energy charge, pass-through charges, levies and VAT.
Why is my Kenya Power bill higher than the tariff rate?
The published tariff is only the base energy charge. EPRA adds pass-through charges for fuel, foreign exchange and inflation, plus the WARMA, REP and EPRA levies and 16% VAT. On the domestic high-consumption band the base charge is KSh 19.08 per unit, but we estimate the all-in cost at around KSh 29.19.
What is the fuel energy cost charge on my bill?
It passes on the cost of running thermal power stations. It changes every month with fuel prices and with how much thermal generation the grid needed, so it tends to rise in dry periods when hydro output falls.
Source: EPRA / Kenya Power schedule of tariffs. The all-in figure is our estimate on the domestic high-consumption band, including pass-through charges, levies and 16% VAT. Check your own bill for your current rate.