Energy & Sustainability Calculators

Energy costs have become one of the most pressing household concerns in the UK. With the Ofgem price cap adjusting quarterly and the government pushing towards net zero, homeowners face a complex landscape of tariffs, technologies, and incentives. Making smart energy decisions requires understanding both your current consumption and the payback periods of efficiency improvements.

The foundation of any energy plan is knowing what you spend today. The energy bill calculator breaks down your annual gas and electricity costs using current unit rates and standing charges under the Ofgem cap. The electricity cost calculator lets you drill into individual appliances -- your tumble dryer, electric shower, or home office setup -- to see which devices are costing the most. The gas cost calculator does the same for gas-powered appliances and heating. The watt calculator converts between watts, kilowatts, and kilowatt-hours, which is essential for comparing appliance specifications with energy tariff rates.

Heating typically accounts for the largest share of a household energy bill. The boiler size calculator determines the correct output rating for your home based on the number of radiators, bathrooms, and the property's size, helping you avoid the common mistake of installing an oversized or undersized system. The heat pump sizing calculator models the alternative: an air-source or ground-source heat pump sized for your property's heat loss characteristics. The insulation savings calculator then shows how upgrading loft, cavity wall, or floor insulation reduces your heating demand and shortens the payback period on any heating system upgrade.

Solar panels represent the most accessible form of home energy generation. The solar panel ROI calculator estimates annual generation based on your roof orientation, panel capacity, and regional sunlight hours, then projects the payback period against your electricity tariff and any export income. The solar battery storage calculator adds a home battery to the model, showing how storing excess daytime generation for evening use increases your self-consumption rate and accelerates the return on investment.

The shift to electric vehicles adds another dimension to home energy planning. The EV charging cost calculator compares the cost of charging at home on your current tariff, at the workplace, and at public rapid chargers. For many households, combining a home charger with solar panels and an off-peak tariff delivers remarkably low running costs.

The electricity consumption calculator estimates your total household usage from your appliance inventory, helping you identify where to cut back. The greenhouse heating calculator serves gardeners who need to keep a heated growing space through winter, modelling the energy cost of maintaining a target temperature. Finally, the carbon footprint calculator quantifies your household emissions from energy, transport, and lifestyle choices, giving you a baseline to measure improvement against.