It Can be Done – but not Without Solar
These missions include:
- Using Artificial Intelligence in the Diagnosis and Treatment of Chronic Diseases
- Meeting the needs of an ageing society
- Reducing Energy Use in Buildings, and
- Zero Emissions Vehicles
Unpacking What The Buildings Mission Means
1. ‘use of energy’
Up until now, the energy performance of new homes for Building Regulations has been assessed in terms of carbon dioxide emissions rather than energy. The argument for this has been persuasive – that there are UK carbon budgets to aim for and policies should be directly targeted towards achieving this.
Secondly, and increasingly, the time of day that you take off electricity from the grid affects the carbon intensity (and price) of your energy. Smart technologies are available that control energy use that has flexibility in its timing (technologies such as heating, running a washing machine, cycling a fridge freezer, charging an electric vehicle or discharging a domestic battery). Though consumers are likely to favour technologies that lower their energy costs, periods of low wholesale energy prices tend to coincide with periods of low demand and therefore a high proportion of renewable energy input. So these technologies will reduce carbon emissions and bills.
As an ‘energy consuming product’ it makes far more sense for regulations for buildings to move to energy consumption rather than carbon emissions . Of course, the lower the energy consumption, the less energy is needed and the easier it will be to lower carbon emissions in the electricity supply.
2.’compared to today’s standards’
Progress on carbon emissions is often measured against 1990 levels – the base year for Annex I parties to the Kyoto Protocol, the countries that signed up in 1997. The UK Zero Carbon Homes policy was enacted in 2007, and progress on energy efficiency standards for buildings has been measured relative to a building constructed to 2006 building regulations.
Improvements in energy efficiency of new build homes has been less than impressive. In the 12 years since 2006, the regulated carbon emissions from a new home built in England is only 29% lower than a house built in 2006. Scotland has pushed further forward, homes built here achieve carbon emissions levels 45% better than 2006.
Significantly, the comparison will be relative to today’s performance levels. Progress to date will not count towards the mission.
3. ‘include a building’s use of energy for heating and cooling and appliances’
Until now, Building Regulations have only including ‘regulated’ energy – that used for heating, hot water, pumps fans and fixed lighting. In homes the regulations ignore energy used for cooking, fridges, freezers, washing machines, dishwashers, clothes dryers, audio visual equipment, IT equipment, plug in lighting and charging battery powered devices.
Housebuilders argue that they shouldn’t be held responsible for the electrical equipment that people use in the homes they build, and the government has up until now accepted that argument.
But why stop there? Surely housebuilders cannot be held responsible for how often people choose to take a shower, or the fact that they don’t want to wear thermals and down jackets while they’re watching TV. The precedent of taking an average for domestic hot water use and internal temperature is well accepted, so there’s no reason why we shouldn’t regulate based on an average electricity use for appliances and gadgets too.
Achieving the Mission
2. The inclusion of energy use by appliances means that the target simply cannot be achieved without some element of renewable electricity generation on the building.
3. The requirement for on-site renewable generation will be even more the case for buildings with form factors that give lower heat losses such as terrace homes and apartments – here there are less gains to be made by improved building fabric and more efficient heating systems.
4. Gas heating currently has Primary Energy Factor (PEF) of 1.222 whereas electricity has PEF 1.738 (SAP10 figures). Unless the PEF for grid electricity falls over the period, a move to electric heating technologies from gas heating will have smaller benefits if the metric is Primary Energy. The more renewable generation on buildings, the more contributions these can make to reducing the PEF of grid electricity.
5. In recognition of the above, forthcoming updates to building regulations should be framed in a way that encourages the use of solar PV on new buildings.