Fuel Poverty in the UK
Fuel Poverty is a topic of increasing importance, and an issue every housing professional will be familiar with. The term has now entered the public lexicon, and every winter we see headlines about those forced to choose between ‘heating and eating’.
The government has identified a target of improving as many fuel-poor homes as possible to an EPC rating of C or above by 2030. In 2016 approximately 2.55M households (11%) were in fuel poverty. This statistic has remained fairly constant, between about 10 and 12% since 2003. The fuel poverty gap however, almost doubled between 2003 and 2012. The increase was largely driven by energy price rises, and while real-terms price reductions between 2014 and 2016 resulted in more encouraging statistics, it is expected that energy prices will continue to rise in real terms for the foreseeable future.
Fuel poverty therefore depends on three separate factors: household income, energy prices, and the energy efficiency of the home. As designers, we can only realistically influence one aspect – home efficiency. Happily, there is much we can do in this area to promote positive outcomes.
Delivering truly efficient homes
With the rise in importance of energy efficiency in response to several issues including fuel poverty, a new breed of engineer has evolved: designers that don’t simply add systems to an architect’s plans, but work in an integrated way to design the fabric of their buildings to achieve energy efficiency. M&E designers can reduce fuel poverty by drawing together all aspects of energy usage in a holistic way. Mechanical design is no longer simply about selecting and sizing heating plant, or checking a few u-values and filling out a SAP worksheet.
One of the most important tools at our disposal has been used for decades to engineer heating systems – the humble heat loss calculation. The most basic version of this method takes the insulation values and geometry of a dwelling to size boilers and radiators. Additional factors such as thermal bridges and heat from the sun and cooking, lighting etc, can increase the accuracy of these calculations and this is the essence of how heating energy prediction tools work. Those familiar with them will recognise the above as a description of SAP (which underpins Part L and many SPG policies), the Passivhaus Planning Package (PHPP) and other energy modelling tools.
The power of Passivhaus
The ‘fabric first’ approach simply takes these methods and looks through the other end of the telescope. Instead of taking a rigid design and figuring out how much heat a building loses, we set a target for heating energy and, using our knowledge of construction and our simple but effective model, work with the rest of the design team to refine the design. The Passivhaus Standard takes this approach to its logical conclusion, and enforces a rigorous QA process to ensure the level of workmanship matches the attention to detail in the design, removing the performance gap.
This means today’s engineers must have a greater understanding of the design and implementation of building fabric, and be prepared to help, and sometimes challenge, other members of design teams to deliver the radical levels of energy efficiency that are possible.
It’s not just the tenants who benefit from this approach. Driving down the demand for heating energy is one of the most effective ways to reduce carbon emissions. Furthermore, Hastoe Housing says that it has zero rent arrears in its new Passivhaus Certified homes, which can also justify an uplift in property values of 10%.
Examples of true efficiency
In the last 2 years, our team at Greengauge has delivered three regeneration sites with Bristol City Council, each of which has received very positive feedback in post-occupancy evaluation surveys. A series of flats and bungalows, which are amongst the first to be built by the council for over twenty years, were designed to the Passivhaus Standard. Despite falling slightly short of the necessary airtightness, the buildings are performing very well. The key take-away from these projects is that many residents are yet to switch on the heating. What could be more efficient than that?
Its sometimes easy to forget in the consultant’s world of spreadsheets and thermal models that this level of energy efficiency makes an enormous difference to people’s lives – something my team and I are very proud of.
Source for fuel poverty stats: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/719106/Fuel_Poverty_Statistics_Report_2018.pdf
