Earnings & Savings
You will be able to receive payments for the heat you generate from a solar water heating system through the government’s Renewable Heat Incentive.
Solar Thermal is eligible for the Renewable Heat Incentive (RHI).
The RHI is very similar to the FIT (Feed in Tariff) scheme for renewable electricity; however the RHI only applies to technologies that generate renewable heat.
|Savings and Payment table|
|Fuel Type||Annual Saving (£)||RHI Payment (£)||Total Saving (£)|
|Gas||£ 50||£ 400||£ 450|
|Electricity||£ 85||£ 400||£ 485|
|Oil||£ 50||£ 400||£ 450|
|Solid||£ 65||£ 400||£ 465|
Savings & Cash Flow Analysis
- Gas prices of 4.5 pence (£0.045) per kilo watt hour of energy
- Property with 4 people
- Average hot water consumption of 60 litres per person per day
- Dishwasher of 20 litres of hot water at 45 degrees per cycle four times per week
- Washing machine of 30 litres of hot water at 45 degrees per cycle three times per week
Therefore we can calculate that the Hot Water requirement is:
Hot Water required:
4 persons x 60 litres = 240 litres
+ (20 x 4)
+ (30 x 3)
= 170 litres / 7 = 24.2
= 264.2 litres per day
From this, we can calculate their daily Hot Water “Power” Requirement:
= 240 + 24.2 = 262.2 x 45 = 11,889 per day
= 11.9 kilo watt hours (kwh) per day
Therefore, the cost to power their hot water is:
£0.04 x (11.9kwh x 365 days) = £195.45
- The house has a Solar Thermal system at a cost of £4,000 fully installed.
- The system has an efficiency of 70% and will therefore provide 70% of their annual Hot Water needs.
Thus, we can calculate their annual savings as being:
Annual Saving = £195.45 * 70% = £136.82
Now let’s add the RHI…
Please see the Energy Saving Trust website for tariff details: