​Making Smart Energy Saving Choices:​ A guest blog by Kuppa

This guest blog explains how Perenna’s Retrofit Calculator helps you save energy. 

We are making it easier to save money, live sustainably, and enjoy a cosier home. 

Home energy costs are in the spotlight again. While prices might drop slightly in April and October 2025, high energy costs are likely to stay. (BBC) ¹ 

But it is not just about rising costs. The way most of us use energy to heat our homes in the UK is bad for the planet too. Most homes (88%, Uswitch) ² burn gas to heat hot water and power heating. 

At Kuppa, we are working with Perenna to help you save energy, and switch to renewable sources of heat and power. Better for you and the planet. And with Perenna, adding solar panels or a heat pump can even help you to save on your mortgage. You just need to opt in to the Retrofit Discount Feature.

What is the Retrofit Calculator? 

Perenna’s Retrofit Calculator can help you make smart choices for your home. In just a few minutes, you will see recommendations, costs and potential savings for energy upgrades tailored to your home. 

It also shows you where you could make bigger upgrades, like swapping a gas boiler for a heat pump. Or where you could insulate to stop heat leaking through walls, roofs, and floors. 

It checks key details like how your home is built, how it is heated, and how you use energy. 

Then, it shows you the best ways to cut costs and improve efficiency. It gives you clear, actionable suggestions to help you get started. ​     ​ 

What does the Retrofit Calculator have to do with mortgages? 

When you make your home more energy-efficient, you could find that your energy bills go down*.

For example, if you install solar, you produce power which you can then use to run appliances. And you may find that some sources of heating, like heat pumps, are more efficient than a gas boiler. The Retrofit Calculator estimates cost of upgrades versus the potential savings.

Lower bills and a greener home can also help with your mortgage.

Perenna rewards you for making upgrades. Check out the retrofit discount feature  to see how you could save on your mortgage, save on energy usage and help the planet when you remortgage. 

Want to get started? Try the Retrofit Calculator! 

*Perenna cannot guarantee energy bill reductions 

Guest blog by Kuppa.

You could lose your home if you don’t keep up your mortgage repayments. 

Correct at time of publishing. 

Footnotes:
1. What is the energy price cap and how are gas and electricity bills changing? – BBC News 

2. Uswitch report on UK home energy use.