‘My mortgage is about to skyrocket – can I afford to go green?’

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Kevin Jones, from Hereford, desperately wants his home to be green – after all, he has spent a good deal of his working life pushing companies towards net zero deadlines far sooner than the Government’s own 2050 target.

After 23 years in the military, Mr Jones, 54, became a finance manager, tasked with finding ways to improve his company’s energy efficiency to meet its shareholders’ desire for zero carbon emissions by 2030, saving them £3.8m. Now on the cusp of moving to the RSPCA, Mr Jones wants to make his home as green as his career.

He says: “I thought at the end of the day, I need to do what I do at work at home. I have all the ideas – the only drawback is the cash issue.” 

Mr Jones says his fixed-rate energy deal recently expired, doubling his bills as a result. His fixed-rate mortgage is also set to run out in September – an uninviting prospect given interest rates remain high.

Mr Jones’s home is roughly 60 years old. Originally built in 1962, it already has some of the hallmarks of a net zero home: chief among which is a hybrid car, bought on finance. He and his wife are frugal with their energy use, opting to “put a jumper on rather than the heating”.

Now Mr Jones is now lining up a few more improvements, including a fully electric car, but his big dream is to install solar panels. The cash issue remains, however, and Mr Jones estimates his budget to be around £5,000 at a push, assuming a system will one day pay itself back.

“I know I’ll need a battery as well, and I am hoping the payback will be around five years,” he says. Mr Jones is aware such a large investment will mean cutting back in other areas. “I still want to live comfortably, but maybe if we miss a couple of holidays or something we can afford it,” he suggests.

To help with this, Mr Jones has moved onto a specialised EV energy tariff, which will charge him less for the electricity he uses at off-peak hours. The tariff saves Mr Jones £150 a month, he claims, as he charges his car overnight when rates are cheaper.

“I’ve done all the quick wins,” he says. “I’ve got loft insulation, all the lights are LED, but the day-to-day running of the house and the mortgage are not cheap.

“I know all the good things that net zero can bring, but just cannot seem to get to the next level.”

Paul Ansell, EPC assessor at Greenfish Consulting, says: 

Mr Jones’s property is a 1960s semi-detached house with noticeable new extensions built around 2018 – these would have been built to building regulations, so should be fully insulated and will have reduced heat loss area to the ground floor.

However, the areas of the original build are uninsulated cavities. I would recommend this be the first area of improvement as, at the cost of between £500-£1,500, it could bring a saving of around £361 a year.

This would not only gain the EPC 5 Points, but also improve thermal comfort by keeping the heat in and the cold out, reducing the amount of energy he uses and therefore lowering his carbon emissions.

After having a nice chat with Mr Jones, I learned he is fully aware of net zero and its effects on the climate as, for his work as a sustainability champion, he has campaigned for his workplace to have solar panels installed. 

He is using his research and knowledge to improve his home: he has already looked at solar panels for his own property and has invested in a hybrid car. He told me he is now looking at an all-electric motor and having a charging point installed at the property.

I did notice the new extension at the rear, and the kitchen has electric underfloor heating which is 30pc of the total floor area. This drops points on an EPC as, even though it is 100pc efficient, it is three to four times more expensive to run compared with radiators or a wet underfloor heating system. This is purely down to the fact that the cost of electricity is higher than natural gas per kWh.

The loft space is fully insulated with 250mm fibreglass loft insulation installed and certified by a local company.

Installing solar panels can add anything up to 10 points to the EPC depending on kW peak and number of panels installed. This can cost anything between £5,000-£8,000 and can save on average around £676 a year.

This property achieved an EPC rating of D59.

Ian Mather, renewable heat expert at British Gas, says:  

Mr Jones’s home is in really good condition, with a wraparound extension on the rear and side off the back of the garage. The extension is modern, and its walls and roofs are insulated.

He is keen to improve the efficiency of his home and do his bit for the environment. Disruption and cost are key considerations, as they are for most homeowners, so with this in mind, my recommendations have been tailored to Mr Jones’s needs.

The home’s electricity demand is on the low side, however an EV charger is due to be fitted to support Mr Jones’s recent change to a plug-in hybrid car. Solar panels are a good option for him and with his roof being east-west orientation it is perfect for solar panels – an array can be fitted on both aspects of the roof. 

Although south-facing has always been considered the optimum orientation for solar panels, east-west using two arrays is very effective and can offer a more even generation curve than south-facing on its own. 

A suitable solar option would be 4.8kW in size with a 5.12kW battery. This will cost Mr Jones £10,800 and would provide a return on investment in 12 years. 

The self-consumption figures (how much of the solar energy generated that is used by the homeowner) on the solar panels will appear lower on the prediction as they are based on current energy usage. 

However, once the EV charger is fitted this will help to boost self-consumption and maximise energy and cost savings. I would therefore advise installing an EV charger that can be optimised for solar panels.

The main house is cavity-walled without insulation – although the efficiency of the home would be improved by having cavity wall insulation installed, the home is in a high exposure area (subject to more adverse weather conditions) so if this were to be pursued, a detailed survey would need to be completed, ensuring the right material is specified for these conditions. 

The front wall could present an issue as the stonework under the front room window would need to be checked to ensure there is not an uneven surface for materials to snag on, or a narrow cavity section. 

An alternative option would be to install internal or external insulation, although this would be considerably more expensive. 

Mr Jones’s home is heated by a modern condensing combination boiler, apart from the kitchen and dining room which are heated by electric underfloor heating and not the main heating system. This solution is working well for him and he really likes how the underfloor heating performs.

A heat pump in the future would be a good way to reduce carbon emissions, but this should only be considered once the wall insulation has been addressed as this will impact the sizing of the unit and the design temperature, which is directly linked to the efficiency of the system.