Professor Phil Jones works at the Welsh School of Architecture at Cardiff University where, over the last 12 months, they have designed, built and are monitoring the UK's first energy-positive house.
Interview with Professor Phil Jones
Phil Jones' background is in building physics, but over the last 15-20 years he has been working as an environmental designer on a number of projects, on both a small and urban scale.
As part of the University's Low Carbon Research Institute, they have been developing a number of technologies in partnership with industry, and have designed and built a home with the aim of it producing more energy over the year than it uses.
It has Taken Just 18 Months to Design and Build
From previous projects that they've worked on, they knew the technologies that they wanted to optimise into the process.
The Wales European Funding Office provided some of the funds which needed to be spent fairly quickly, so that provided an incentive to get it done!
They managed the project themselves but employed a construction manager to oversee the site. That way they were able to keep control of the project and ensure they remained within budget.
Integration of Technologies and Architecture
A systems approach has been used to integrate the technologies together, and to integrate those technologies into the architecture. The energy demand of the house is close to Passivhaus levels, and both thermal and electricity energy storage has been incorporated. It utilises SIPs panel construction and has a render applied to the outside, except for where the thermal air collector is.
Solar electricity – used for the lighting and small items, runs the heat pump for the heating system, charges the batteries and heats the water. Any excess is exported back to the grid. The PV panels form the south facing roof of the building.
The thermal system – air is brought into the building using a transpired solar collector (an air collector wall on the south elevation). The heating in the house is from the air being pre-heated by the sun, picking up heat from the MVHR and being topped up by a heat pump. The heat pump uses internal air, so is more efficient than using an air source version which works on external air temperatures.
The ‘buildability' of the design is aided by the components being readily available locally, and local skills and contractors being used.
The House is Around 75% Autonomous
This is based on their predictions. There will be periods when the house will draw from the grid, but over the course of the year it is estimated it will put back in roughly 70% more to the grid than it will take from it.
Battery Technology is Developing at a Fast Pace
They opted for lithium batteries as, although they were more expensive, they were lighter and had more capacity for the size. They're bolted to the wall and don't need any maintenance from the occupants. Phil notes that since building the house prices have fallen by around a half. He says Tesla for example have produced a 7kWh lithium battery for the housing market for around £3500, with costs predicted to come down further.
Cost Increases Have Been Offset by Cost Reductions
Some things have inevitably cost a little more, such as the heating and battery systems, but there have also been savings. Using the ventilation system to heat the house means that there are no radiators or wet services around the building. No radiators also means that the room spaces can be more flexible.
With the PV panels being the actual roof, it has not been much more expensive than a normal roof, and the air collector forms part of the wall construction.
Costs are expected to be around the price of standard social housing, or the price of something that has been produced by a quality private developer.
Solcer House Has Been Well Received by Visitors
Feedback from the public that have been to visit the house or seen the details on the internet has all been very positive. The principles that have been used in the building can be adjusted to suit different aesthetics and different building types.
While volume house builders have been interested in seeing the house, Phil suspects it is not something they will be trying at the present time. They won't do anything new until such times as they have to.
Builders of social housing have been more interested as they can appreciate the performance over time and the sense of having a building that people can afford to live in in the future.
Smaller scale developers are likely to see this as a market opportunity, to meet the demands of people who are confused as to why all houses can't perform like this one.
Find Out More
This video explains more about the construction of Solcer House:
We featured Jackson Moulding of Ecomotive in Episode 77, where he spoke about the Ashley Vale group self build scheme which initially had to fend off a large developer in order to secure their plot of land.
Ecomotive are putting on a week-long series of talks and workshops in Bristol, aimed at inspiring people who want to go down this route and looking at some of the challenges they can expect to face. Ben Adam-Smith has been invited along on Saturday 5th December 2015 to share what he has learned so far.