Home energy technologies are developing all the time. Companies come up with new technologies, or new features for existing technologies, or just new ways to use the systems we already have. And new evidence is emerging all the time on how well systems work, when they make sense and when they don’t.
Here are some recent innovations, and a few that have been around for a while but which we haven’t been able to verify yet.
Underfloor insulation applied by a robot
Q-Bot has created a robotic device that applies underfloor insulation to suspended timber floors. A remotely operated device applies spray foam insulation to the underside of the floor.
The robot is inserted into the space under the floorboards via an airbrick or a small access hatch. It surveys the space under the floorboards, then sprays the foam to the underside of the floorboards, which expands to fill the gaps, while maintaining the ventilation space below. According to its owners and creators, the technique can reduce heat loss through the floor by up to 90%, leading to significant savings on heating and reduced carbon emissions as a result.
It won’t be suitable for every home, but this could provide an interesting, less disruptive mechanism for insulating beneath your floorboards.
Air source heat pumps are a fairly well established technology, but their efficiency can drop significantly if they have to draw heat from particularly cold air, or provide heat at a particularly high temperature. A hybrid solar heat pump uses a solar thermal collector to preheat the air before it enters the heat pump, so the heat pump can then produce water at a relatively high temperature without having to work too hard. This is ideal for producing domestic hot water.
The principle is entirely sound, and the heat pump should operate at a high efficiency and so use only a small amount of electricity. But we don’t have any independent performance data to estimate what the running costs would be and how this would compare to the cost of buying and installing a system.
You should bear in mind that the average household bill for providing hot water is around £80 a year, so if you buy a hybrid solar heat pump that only produces domestic hot water it can’t save more than this on your fuel bills.
These are different to hybrid solar heat pumps. They are conventional heat pumps, but with a secondary heat source alongside, usually a gas or oil boiler. The idea is that you can switch to using the boiler instead whenever the heat pump is unable to provide all the heating requirement, or to operate at a reasonable efficiency.
Some people describe these as bivalent systems, but that name can be used for any heating system that uses two different fuel sources.
We can’t currently advise whether there are any situations where it would be better to fit a hybrid heat pump rather than a heat pump on its own or a gas or oil boiler on its own.
PVT is another hybrid system, but this time it’s a solar PV panel (to generate electricity) with a solar thermal panel (to produce hot water) underneath. The theory says that the solar thermal panel draws heat from the PV panel, which cools it down and makes it more efficient, so you get more electricity generated while also getting some hot water. The hot water will have to be relatively low temperature though if it’s going to affect the PV efficiency (50 degrees Celsius instead of 70 degrees like in conventional systems). You’d then need to have a backup system (such as a boiler, a heat pump or both) to get hotter water, for washing or cleaning for example.
Solar PVT systems aren’t eligible for either Feed-in Tariff or Renewable Heat Incentive payments. They are usually used in very energy efficient homes aiming for zero energy bills, especially when roof space is relatively small, as this system makes the most of the solar energy to create both heat and hot water. Another common use is pool heating.
Sometimes it can be difficult to make sure you’re switching to the best deal for your energy supply if you’re not exactly sure how much energy you’re using. And this is going to get harder still as energy suppliers develop new variable tariffs that charge different rates at different times.
So why not buy a robot to monitor your energy use and do the switching for you? Systems like this are now coming onto the market.
As the UK looks to transition to net zero by 2050, policies will also be critical in reaching that goal. Here, we look at some of the more innovative and progressive government policies from around the UK in recent years.
Standards for the Private Rented Sector
The UK Government is currently consulting on the possibility of introducing ambitious minimum energy efficiency standards for the private rented sector in England and Wales so that these homes would have to reach EPC Band C by 2025 for new tenancies and 2028 for existing tenancies. Currently, the private rented sector is the worst performing in terms of energy efficiency and this proposal is welcome. We had recently called for a target between 2026-2030 depending on the level of investment so are pleased to see the UK Government being ambitious in this area.
The UK Government is deciding on the exact detail of the Future Homes Standard which should come into force in 2025 and apply in England. It will be a series of ambitious standards for the new build sector which will greatly improve the energy efficiency and build quality of the new housing. Government most recently consulted in late 2019 on Parts L and F which focus on energy efficiency and ventilation. Read more on this here.
The Welsh Government has recently published its Local Ownership of Energy Generation policy paper. This sets out the Government’s ambition for some degree of community ownership to be part of any new energy projects from 2020 onwards and 1GW of renewable electricity and heat to be locally owned by 2030. By 2020, the Scottish Government expects to see at least half of newly consented renewable energy projects having an element of shared ownership. Scottish Government also has an ambition for community benefit to be equivalent to £5,000/MW. Work is ongoing in Scotland into the possibility of translating ambitious EU law regarding the rights of ‘Energy Communities’ into Scottish law.