Modern ideas meet heritage buildings
How do you more than halve the energy consumption of a heritage building in just seven years. And what are the special problems faced by facility managers responsible for heritage buildings. Lizzie Phillips of Cavendish Engineers has the answers.
Facility managers have been facing their greatest challenges in recent years. Government targets to reduce building energy consumption by 2020 means that both public sector buildings and commercial buildings are feeling the pinch to deliver.
According to the DECC (Department for Energy & Climate Change) UK Energy Brief 2011, the UK has the second lowest energy ratio in the G8, behind Japan, which shows that there is definitely some area for improvement.
Yet can any building really reduce its energy use whilst delivering quality operative maintenance?
Admittedly FMs today have it tough. The change in both climate and weather has added extra problems for building-services teams. For example, March 2012 was the third warmest in records dating back to 1910 and the warmest since 1957, meaning an adjustment to building temperature control.
In the south of England, where we have had a drought followed by rain, the hard ground has been unable to cope with the heavy rainfall that followed.
Older buildings and Grade Listed buildings can be more susceptible to these conditions — and don’t come without their challenges. However, with the development of new energy technology, both old and new can mix to create an efficient and reliable working environment.
There is a whole host of energy-reduction technologies on the market, many of which are improving continuously.
Technologies such as air conditioning have improved tremendously on their energy rating. For example the typical energy-efficiency rating for air-conditioning and heat-pump systems is A or B, whereas five years ago it was C or D.
New engineering technologies have also enabled many of a building’s original features to be restored. For example more recently the flag pole and the column facade of 9 Millbank in London were repaired using high-tech materials, but modelled on the original parts/features.
Good-quality maintenance is a vital player in reducing energy. Giving maintenance teams key targets that can be measured and, therefore, managed, enables all parties to understand the end goal and encourages proactive rather than reactive thinking.
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| Dating from 1928, the landmark 9 Millbank building in London has seen its Display Energy Certificate improve from G165 to D82 over seven years, with the help of M&E maintenance and engineering support from Cavendish Engineers. |
Measuring can be achieved through metering, looking at previous energy bills and identifying areas which are not effective or have a high energy output. New technology that is installed needs good aftercare to realise the full benefits. It is too easy to install a new energy product without maintaining or monitoring it.
Since 2001, Cavendish Engineers have provided M&E maintenance and engineering support at 9 Millbank in London. Originally built in 1928, it is a true landmark building, establishing a powerful and imposing architectural presence on London’s skyline. Cavendish Engineers recently collected an award for Best Retrofit Workplace Building at the Green Build Awards for reducing its energy consumption by 56%.
In 2001 Ofgem (Office of the Gas & Electricity Markets) occupied the building, and today it accommodates about 850 employees as well as hosting parliamentary dignitaries, including the Secretary of State for Environment, Food & Rural Affairs.
Cavendish Engineers have worked with both tenants to create a working controlled environment whilst reducing their costs. Between 2004 and 2011 the building has reduced its carbon consumption by 56%.
Our joint collaboration has meant that Ofgem has improved its Display Energy Certificate from G165 to D82 over seven years. Ofgem’s impressive energy results have paved the way for other Government buildings and Westminster buildings.
In addition to continuous improvement in energy and FM management, Cavendish Engineers has incorporated over 57 different energy reduction strategies in the last 10 years, of which 37 of include new plant technologies. For example; although low-energy lighting is now commonplace, in 2001 it was not well regarded in everyday FM. Ofgem installed PIR (passive infra-red) motion detectors for light switching between 2001 and 2009, and more recently the lighting for conference rooms has been replaced with LEDs.
In 2002, this became the first Government building to install a CHP system, enabling other Government buildings to follow suit. In 2007, Ofgem switched to a 100% green electricity tariff and in 2008 installed two voltage power optimisers.
From a study of the building’s gas profile at Ofgem, Cavendish found that the gas consumption was the highest contributor to overall energy consumption. This was primarily due to the inefficient use of CHP and the inappropriate control and application of a boiler array.
Whilst we installed new equipment (which saved 14% per annum and about 60% direct consumption), we also introduced night setback to provide additional savings. Night setback means that we don’t allow the buildings to get colder than 17°C, enabling us to optimise the thermal profile.
With 850 occupants it was possible to phase shift the energy input from the fabric stone energy and use the people as a heat source. This meant that around 13 kW of heating was not required.
Ofgem encourages staff to embrace their low-energy ethos by offering up to £500 bike loans and bottling their own water using recyclable bottles. Even their new office chairs are made from 86% recycled materials and are themselves 96% recyclable.
Heritage buildings have pride and place in our architectural history. It is these new changes to technologies that will enable us to enjoy them for many years to come.
Lizzie Phillips is business development executive for Cavendish Engineers.
