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Part L and those Energy scares graphicThe recent issues surrounding the big five Energy suppliers has put our energy security problems into sharp focus. Last year the demand for heating fuel in the run up to Easter exposed the fragility of our critical energy infrastructure as it emerged we had just two weeks of gas supplies available as temperatures plunged.

During the very cold winter of 2010/11, we had a similar scare when Centrica warned the Government that it was just about to run out of gas. Thankfully, we then had the warmest January and February on record and disaster was averted.

However, it’s obvious we can’t keep riding our luck. The chief executive of energy regulator Ofgem warned the industry last year that things were looking bleak. Alistair Buchanan told the CIBSE Annual Lecture that, although the Government’s long term energy strategy might be sound; the short to medium term situation was alarming.

“The UK’s power demand is falling, but our capacity is falling faster,” he told the Institution’s members and guests.

Wakeup call

Mr Buchanan explained that the country is running out of Electric energy because renewable power generation was moving “way too slowly”; the programme to build nuclear power stations was delayed by funding problems; and the carbon tax (in effect from last April) would put coal-fired power generation out of business.  

In the next two years we will lose 11% of our power generating infrastructure as more coal and old-style gas-fired power stations are closed down as we seek to meet our legally binding commitments to cut CO2 emissions.

Energy buyers are looking everywhere for reliable and stable gas supplies to keep our remaining power stations operating as our own North Sea stocks dwindle. It is going to be very expensive if we become hooked on imported gas – whether piped in, fracked or liquefied – but we will have to pay the price or face power cuts.  Additionally with the issues currently going on in Ukraine and Russia – one of our biggest suppliers is causing further problems

With time running out we simply must get really serious about the demand side and start using considerably less energy – without huge strides in conservation we cannot close the energy gap.

Fortunately, as the cost of energy soars, the business case for energy efficiency improves. Buildings are responsible for over 40% of total energy demand so residential and commercial building occupants will see their energy costs rocket in coming years.

Underpinning the economic driver for energy conservation are the changes to Part L of the Building Regulations, which came into force in October last year. Taken together, economics and legislation can deliver the huge changes needed to the way we manage energy use and heat our buildings. 2014 is looking more and more like a pivotal year for energy efficiency.

Part L 2013 has, sensibly, taken a more flexible approach than previous versions to make it easier for the building services industry to deliver a broad programme of low energy buildings.  It has set a range of target improvements to achieve an aggregated 9% improvement (compared with the 2010 version of Part L) for new non-domestic buildings depending on the type of structure being constructed. The Government hopes this will make it easier for design engineers to produce solutions across a wider range of buildings and, therefore, deliver an overall improvement for new build.


To achieve the most energy efficient solution, engineers need flexibility particularly in ‘hard to treat’ buildings like warehouses and retail premises, which is where the lower targets will apply. The highest ratings will only be applied to buildings like offices and modern housing where design enhancements can be applied cost effectively.

This energy saving across new and existing buildings would dramatically reduce demand on the energy grid and it is in existing buildings where the biggest and fastest changes can be made. The new Part L also includes energy efficiency targets for refurbishment work, but here too a flexible approach has been taken to ensure more buildings can be improved. 

Condensing boilers will be required to reach targets in many refurbishment projects – and in all new builds, but in the retrofit commercial water heating sector there is some room for manoeuvre. Design engineers have, been given some leeway in this area to keep costs realistic and non-condensing systems – still of sufficiently high energy performance – will be permitted to ensure low energy improvements are made.

Existing regulations have tended to incentivise the use of individual technologies failing to give enough credit to the performance of complete building systems. By setting targets for fabric performance, Part L is starting to move the argument in favour of the complete building approach which suits the all-round expertise of building services design engineers.

It is similarly encouraging that the review of the Renewable Heat Incentive (RHI) has also taken the overall performance of complete building systems into account.

This is not a case of government interference adding unreasonable burdens to industry, but simple common sense that can lead to dramatically lower operating costs for building occupants and, even more importantly, help to keep the lights on.