Working out payback time in 2026.

The meter that runs backwards no longer exists. It used to be that your meter turned back whenever you produced more than you used, and everything was cancelled out at the end of the year. That system, called net metering, has been abolished for good.

If you put electricity onto the grid today, you receive an injection fee for it, and that fee is clearly lower than what you pay to buy the same electricity back later. Electricity you use yourself, at the moment your panels are producing, is therefore worth a great deal more.

Step 1. What the installation actually costs you, VAT included. For a home older than ten years the reduced rate of 6 per cent applies; for a newer home or new build it is 21 per cent.

Step 2. How much you generate. Work with the yield calculated for your own roof, not with an average from a brochure.

Step 3. How much of that you use yourself. This figure decides everything. A household that is home during the day, or that has a battery, a heat pump or an EV charger, comes out much higher.

Step 4. Work out what you save each year. What you use yourself, you save at your full price per kWh; what you export earns only the injection fee. That sum divided into the investment gives your payback time.

Running your heavy appliances during the day: washing machine, tumble dryer, dishwasher.

A home battery, so that evening use still comes from your own production.

An electric car that charges during the day rather than overnight.

Controls that start those appliances automatically when the sun is shining.

ADW works out your payback time during the site inspection, based on your own roof and your own usage pattern. You get that figure before you decide anything, not afterwards. If it looks unfavourable, we tell you that too.