With the cost of living rocketing, not least of all as a result of rising energy bills, I have been intrigued, as have many of us, by the idea of living in a home with no energy bills.
So, when I was given the chance to visit an Octopus Energy Zero Bills home I leapt at the opportunity – particularly as it wasn't just one home, it was 89 of them.
I don’t really know what I was expecting from the visit. Zero bills just sounded too good to be true but, on the other hand, I also know from experience that Octopus Energy have had previous successes in this arena with some innovative software. I wanted the concept to work, as after all, who wouldn't want a zero bills home?
Article continues belowWhat's different about these zero bills homes?
In the past few years there have been many house building standards introduced to improve the fabric of the building, with the overall aim of reducing the energy consumption of the home.
Whereas the Standard Assessment Procedure (SAP) is the assessment method used for current building regulations, and is key to producing Energy Performance Certificates (EPCs), it will inevitably be replaced in the near future by Home Energy Modelling (HEM) with the full adoption of the Future Homes standard.
Other assessment methodologies, such the Code for Sustainable homes, Super E, Carbonlite, BREEAM and PassivHaus have been created by various organisations to try and improve on SAP and deliver energy efficient homes to as close to net-zero carbon emissions as possible.
However, all of these standards are able to deliver homes to a very high performance specification, but none of them guarantee zero bills for the homeowner.
Octopus Energy's Zero Bills homes on the other hand, are built on the offering that if you follow the specification, fit the prescribed technologies to your home, and hand the control over to Octopus Energy to manage, then they will guarantee you have no energy bills for up to 10 years.
And, while zero bills homes have predominantly been deployed through developers, (over 5000 homes are already approved as eligible for zero bills), self-builders who are undertaking one-off new build homes, can also join the scheme.
Octopus Energy have set a target to have 100,000 zero bills homes by 2030, so there is still time to get involved. Early engagement is key to make sure that you specify the right products, as not all PV, battery systems and heat pumps are compatible.
So what’s the catch I hear you ask. Well, there isn’t one, but, there are some rules. Clearly you cannot heat up your neighbour's house, or charge every electric car in the street for other people, but that doesn't mean they don't come with some impressive renewable energy tech.
What's included in these zero bills home?
The site I visited, Hollymead Square, is a development site being developed by The Hill group in Newport, Essex, and has 89 mixed-tenure energy efficient 1, 2, 3, 4 and 5 bedroom homes, as well as 2-bed bungalows.
All of the zero bills properties have all been installed with photovoltaic solar panels, solar battery storage, electric vehicle charger and an air source heat pump. It's definitely a high-end development, and one of the better sites I have visited.
The rooms in the homes are large and there is a great sense of space in every home I visited. Wet underfloor heating is standard on the ground floor, with radiators upstairs, all designed for the low temperature heat pump systems.
The developers have said that the home insulation level is above current building regulations, with predicted SAP being 113/100 depending on the house type and specification. This compares very favourably against an average SAP of around 85/100 for new homes in the UK, and equates to an A-rating EPC.
The homes also have a SAP CO2 reduction of around 105%, compared with homes built to building regulations Part-L 2021. These particular homes were designed in the early days of the zero bills concept, and have a 5-year zero bill guarantee.
Hannah McCarthy, head of zero bills at Octopus Energy, has also said that she sees no reason why this 5-year tariff, or the newer specification 10-year guarantee, could not be continued after the guaranteed time period has passed.
What are the requirements for these homes to be classified as zero bills?
I was still curious about the zero bills claim and how that worked, wondering if there was some sort of formula that would require a whole field of solar panels and a large room full of solar batteries.
Thankfully, this isn't the case. The process of assessment for an Octopus Energy Zero Bills home involves an individual assessment, taking into account a variety of details, including roof analysis, SAP assessment, orientation and occupancy.
Looking at an average home on this site of around 150m2 floor area, it had between 8kWp to 10kWp of solar PV panels (around 20 to 24 panels), a minimum of 13kW of battery storage, an electric vehicle charger and an air source heat pump designed and commissioned to cover the full heat load of the home.
The annual energy use of the home must equal the annual ‘generation’ from the PV panels over a whole year, and there is an additional fair use allowance of 4000 kWh (units of electricity) per year.
Putting that into perspective, a new build home would be expected to use between 8000kWh and 10000kWh per year. Considering that an 8kWp (south facing) solar PV array should also generate up to around 8000kWh per year then the additional 4000kWh makes the scheme very appealing, and it is also quite clear that there is no apparent ‘catch’.
You would normally expect to generate far more energy in summer and use far more in winter, but as the energy use is based on a whole year, these two can balance out.
What are the advantages of these zero bill homes?
One of the key lifestyle advantages of these Octopus Energy Zero Bills homes is that the homeowner can use energy at any time of day. They can put the tumble dryer on and cook meals whenever they want, as they are not limited to using certain tariffs at different times.
There is no time management required, no need to programme appliances to operate at midnight, and no limitation on the heating during the day in winter. There is also no standing charge, which saves a further 65p a day.
Unfortunately, electric vehicle charging is not included in the scheme. This is charged at the intelligent Octopus Energy rate, but this means you can still benefit from cheaper charging at the off-peak night time tariff.
Homeowners can also leave the scheme if they choose to manage the technologies themselves, there is no tie in and no commitment. The only condition being that you can't leave the scheme every summer to enjoy export tariffs when the sun is shining, and rejoin it in winter.
If things go to plan, it would be nice to think zero bills could be the way we all live in the future.
While we may not be quite at the stage where I say yes, you can turn any home into a zero bills home, in an ideal world, my kids will come to me when they are older and say, “Hey Dad! Remember those days when you used to moan about those things called electricity bills?” And I will say, “Yes, son! They’re a bit like telephones, DVDs and petrol stations….. nobody uses them anymore!”
