Unit Converters

Power Converter

Convert between watts, kilowatts, horsepower, metric PS, BTU/hour and more instantly. Covers car engines, boilers, appliances and electrical systems.

Power Reference — Common UK Applications
ApplicationTypical power (W / kW)Equivalent
LED bulb4–15 W0.005–0.02 kW
Laptop30–65 W
Electric kettle2,000–3,000 W2–3 kW
Electric shower7,000–10,500 W7–10.5 kW
Combi boiler (typical)24,000–35,000 W24–35 kW / 82,000–119,000 BTU/hr
Family car engine (150 bhp)111,855 W111.9 kW / 152 PS
Tesla Model 3 (peak)~250,000 W250 kW / 340 PS

Common Power Conversion Questions

How many watts is 1 horsepower?

1 mechanical horsepower (bhp) = 745.7 watts. 1 metric horsepower (PS) = 735.499 watts. UK car reviews use bhp; European manufacturers often quote PS. The difference is under 1.4%, so a 200 bhp car = roughly 203 PS = 149.1 kW.

What is the difference between bhp and PS?

BHP uses mechanical horsepower (1 hp = 745.7 W). PS (Pferdestärke) uses metric horsepower (1 PS = 735.5 W). 1 bhp ≈ 1.014 PS. The difference is negligible for everyday use. Both are often quoted alongside kW in official EU type approval figures.

How do you convert BTU/hr to kW for a boiler?

Divide BTU/hr by 3,412 to get kW. So a 30,000 BTU/hr boiler = 30,000 ÷ 3,412 ≈ 8.8 kW. Alternatively, multiply BTU/hr by 0.000293 to get kW. Most UK Gas Safe engineers quote output in kW; BTU appears in older or US-origin documentation.

How much power does a typical UK home use?

A UK home's average power demand is roughly 0.35–0.5 kW continuously (around 3,000 kWh/year). Peak demand occurs in the morning and evening with kettles, showers and cooking — total peak draw can reach 10–15 kW. A 7 kW home EV charger (typical wallbox) roughly doubles instantaneous demand.

What power is needed to charge an electric vehicle at home?

A standard UK 3-pin socket provides a slow charge of around 2.3 kW. A dedicated 7 kW wallbox (Type 2, single phase) is the most common home installation. Some three-phase installations offer 22 kW. A 50 kW DC rapid charger (public) and 150+ kW ultra-rapids are public infrastructure rated in kW.