All Solar Calculators

Free UK calculator to estimate how many solar panels your home needs. Uses MCS-aligned irradiance, average British household consumption (2,700 kWh/yr), and 400 W panel specs.

Free EV charging calculator for UK drivers. Estimate kWh drawn, charge time on a 7 kW home wallbox, electricity cost at 2026 Ofgem cap rates, and the savings if you charge from solar PV.

Free UK off-grid solar calculator. Sizes PV array (kWp), battery bank (kWh), and inverter (kW) from daily kWh load using PVGIS irradiance data and MCS-aligned design factors.

Free commercial solar investment tax credit calculator for UK businesses. Estimate your Annual Investment Allowance (AIA), 50% First-Year Allowance, Smart Export Guarantee tariff, and net cost after every business incentive.

Free solar panel savings calculator for UK homes. Estimate 25-year lifetime savings using your annual generation, Ofgem tariff cap rate, SEG export tariff, self-consumption rate, and price escalation.

Free UK solar panel cost calculator. Estimate installed cost from your monthly kWh, peak sun hours, £/W price, and the 0% VAT relief. 2026 MCS, Energy Saving Trust and Solar Energy UK data.

UK EV charging cost calculator using April 2026 Ofgem cap rates and Octopus Intelligent Go off-peak tariffs. Per-session and annual running cost on a 7 kW wallbox plus solar PV offset.

Free UK solar panel output calculator. Estimate daily, monthly, and 25-year kWh production from your array, sun hours, and system efficiency — plus pound savings.

Free solar tax relief and grant calculator for UK homeowners. Estimate the value of 0% VAT (HMRC Notice 708/6), ECO4, HUG2, and council grants on your domestic solar installation.

Calculate how much your monthly electric bill drops after going solar in the UK. Free tool with Ofgem default tariff cap, SEG export rates, and MCS-aligned production figures.

Free solar panel estimate calculator for UK homes. System size, annual generation, gross & net cost (0% VAT), year-1 savings with Octopus Outgoing 15p export, payback and 25-year lifetime savings. 2026 MCS and Energy Saving Trust data.

Free UK solar battery bank sizing calculator. Size your battery in Ah and kWh for off-grid cabins, motorhomes, or grid-tied storage based on daily load and autonomy.

Free UK solar loan calculator. Estimate the monthly repayment, total interest, and year-1 net cash flow on a financed residential PV system using current 2026 lender APRs and Octopus SEG export pricing.

Free UK solar panel cleaning cost calculator. Estimate per-visit, annual, and 25-year cost in pounds — and whether cleaning pays back in extra kWh.

Free UK solar panel installation angle calculator. Compare your roof pitch to the latitude-optimal angle for British weather, see annual yield loss, and find the wedge bracket size needed for flat-roof and shallow-pitch installs.

Free solar panels kWh calculator for the UK. Enter your monthly kWh use, target offset, and panel wattage to see system size, panel count, and bill savings — calibrated to PVGIS-SARAH3 and MCS standards.

Free solar panel payback calculator for UK homes. Estimate the year your system breaks even using your installed cost, electricity rate, Smart Export Guarantee tariff, and realistic Ofgem-tracked rate increases.

Free solar panel ROI calculator for UK households. Estimate payback, lifetime savings, and IRR using your installed cost, tariff, and SEG export rate.

Free solar panel roof load calculator for UK homes. Compare PV array dead load against BS EN 1991-1-1 imposed roof loads in kg/m² with MCS-aligned guidance.

Free UK solar panel tilt calculator. Find the best fixed tilt for year-round, summer or winter generation across England, Scotland, Wales and Northern Ireland.

Free UK solar cable size calculator. Enter voltage, current, and cable run length to get the smallest copper cross-section that stays within BS 7671 voltage-drop limits.

Free UK solar panel charge time calculator. Estimate how many sun hours or days your solar array needs to recharge a leisure or off-grid battery from any depth of discharge.

Free UK solar panel orientation calculator. Enter your latitude, roof azimuth and pitch — see the percentage of optimal yield versus due-south, MCS-style.

Free UK solar voltage drop calculator. Enter system voltage, current, cable length and mm² to see drop in volts and percentage. BS 7671 compliant.

Free UK solar lease vs buy calculator. Compare cash purchase, financed purchase, and rent-a-roof / PPA over 25 years using current 2026 zero-VAT pricing, MCS-installer rates, and Octopus SEG export tariffs.