Zero Bills homes generate more energy than they consume, using a combination of low carbon technologies to guarantee zero energy bills for at least five years.
It’s based on a fair use allowance, which is set at around double the average expected usage. EV charging is currently billed separately at Intelligent Octopus rates.
Customers are not locked into any sort of agreement and are free to leave or switch at any time.
The Kraken smart energy platform takes data from the home’s devices, the grid, and external factors to calculate the best and most affordable way to power the home. This includes factors such as how sunny it is, how much charge is in the battery, the cost of energy in the grid and how much of it is renewable.
The platform automatically selects the greenest and cheapest option and directs that into the home, as well as managing the sale of any excess energy to the grid. This means the network can be supplied with green energy when it needs it most and offset the cost of any the home needs to buy.
We spoke to Octopus Energy’s technical director, Nigel Banks, to find out more about how Zero Bills works and what makes it a viable proposition for the business.
A zero stress proposition
“For the consumer, this is a zero stress proposition,” Nigel said. “There’s no stress about bills going up. It’s currently guaranteed for five years, but we are expecting to extend this to ten, and the tariff may continue beyond then, as long as the equipment is still functioning.
“For Zero Bills to work, the home has to be all-electric which means heat pump, reasonably good insulation, a battery and solar. And the solar array has to be large, typically covering both sides of the roof, with probably an average of 15 to 20 panels per property.
“It needs to be an 8-10kW solar array and a 10- 13 kWh battery.
“It is, typically, only applicable to new homes so far although we are currently looking at the retrofit proposition. We have around 1000 homes that are either built, committed to being built, or in the planning phase.
“We believe we can get to 50,000 homes committed to being built by 2025 as we’re expanding the model globally as well.
“We’re currently trying to work with all major housebuilders as well as smaller building firms to try and develop a Zero Bills standard they can all adopt.
“There are further upfront costs for developers, but we are seeing these homes sell for more, so they should recover their costs, and the home should retain that extra value.”
Commercially viable for everyone
“We think it’s commercially viable for everyone, but we know it’s quite counter-cultural to spend more when a return isn’t necessarily guaranteed. “With this model, we’re trying to show that a low carbon solution is affordable, and is attractive for consumers. It’s about, hopefully, creating a virtuous cycle of housebuilders saying they want to build these homes because people want to buy them.
“It could also help ignite the retrofit market when people see the savings their friends or family members are achieving in a Zero Bills home.”
Octopus Energy has an approved panel of manufacturers to provide the low carbon technology and is adding more to the list.
Developers appoint installers and Octopus Energy works with them to clarify the specifications needed.
“For Octopus, we can guarantee Zero Bills and still get a margin by exporting excess renewable energy to the grid at peak times,” Nigel said. “It’s only really in the last 18 months that the cost of technology has come down enough to make it more viable and I think this will only improve over time.
“There’s the potential to be exporting more power at peak times than importing, but we need to collaborate with the District Network Operators to make this work. The UK grid price varies massively throughout the day, and we’re still turning on the coal plants to meet demand at peak times.
“If we can export renewable energy to the grid at these times, we can reduce our carbon use.
There are also times when there is excess power in the grid, when prices can go very low, and we can make use of that to charge batteries in the home.
“It’s a win all around.”
Zero Bills for the customer
As Octopus Energy technical director, Nigel Banks, put it, ‘Zero Bills’ might currently present a more engaging proposition for the consumer than ‘zero carbon’.
It assumes that even people who can’t or don’t want to implement low carbon technologies would prefer a green home with no energy bills when presented with a choice between the two.
A homeowner’s view
Carolyn Minton is among the homeowners who already live in a Zero Bills home. She moved in to her four-bed Falmouth property, built by Berto Homes, in November last year.
She moved there from a similar new-build which had solar panels and underfloor heating and, when looking to relocate, she was happy to choose an even greener home.
“I think they only had 50 customers on Zero Bills at the time so they were still learning, but setting it up wasn’t onerous at all; they did everything from their end,” Carolyn explained.
“They cancelled my previous electricity supplier and registered my solar panels. I control the heating via an app on my phone. I’ve learned what the optimum temperature is for different rooms. I’m still quite frugal with it, even though the fair use allowance is almost double what the average consumption would be.
“I had oil-based heating before and this is so much better than that. I don’t have to order oil, or keep an eye on the tank or look for the best rate.
I don’t even have to send meter readings for the electricity now and I’ve always got hot water.
“I think as long as the system is built well, you don’t have to think about it at all.
“I have a Vaillant air source heat pump at the back of the house, 16 solar panels on the roof and the GivEnergy battery and inverter are in the garage. Even the router is in the garage.
“I would definitely recommend it. I wouldn’t even look at a house that doesn’t have green energy solutions now. It’s the future. We need to be more sustainable and stop wasting energy. I can’t see why the government hasn’t yet enforced builders to stop putting gas boilers in.”
Image credit: Envirolec
