A new eco-friendly housing development in London is getting the energy for its heating and hot water directly from the Thames in a pioneering community 
heating scheme that could be replicated in many of our major towns and cities.
Ed Davey, the Secretary of State for Energy and Climate Change, visited the site to switch on the heat pump-based heating system in an official launch of the innovative, renewable system late last year.
The £70 million mixed-use development – Kingston Heights, has been created by NHP Leisure Developments on the site of a former power station right in the heart of Kingston upon Thames, and 200 metres from the banks of the river.
The development includes 56 homes for national affordable housing provider Affinity Sutton, plus 81 luxury private apartments that are now being marketed by Redrow Homes London. The 137 apartments, built by specialist contractor and developer, United House, will all benefit from the cutting-edge heat pump system that harvests naturally stored energy from the River Thames. The community heating scheme takes the heat in the river water and boosts it to the temperature required for the underfloor heating and hot water needed by residents.
At two metres below the surface the Thames water never falls below 7°C, even in winter, so we can be certain that it can provide enough energy to heat the apartments,” explains Mike Spenser-Morris, managing director of NHP Leisure Developments and the visionary behind the scheme.
“If we had fitted gas or biomass boilers, then the site would be dumping around 500 additional tonnes of carbon into the atmosphere each year. In addition, because of this system’s exceptional energy efficiency, the equivalent heating cost for a couple living in a one bedroom apartment would have amounted to around £300 a year more.”
The system will draw up to 13 million litres of water each day – the equivalent of five Olympic-sized swimming pools. The river water passes through a state-of-the-art, two-stage filtration process that ensures no marine life can enter the system.
Inside a specially-built plant room adjacent to the river, the water passes through high-efficiency heat exchangers and, once the low grade heat has been harvested, the water is immediately fed back into the river, untreated in any way.
The heat exchangers transfer this low grade heat from the river water to an internal ‘closed’ loop water system and this is then carried 200 metres to a plant room in the apartment building, where Mitsubishi Electric’s advanced heat pump technology boosts the low grade heat to the temperature required for the apartments’ heating and hot water.
Towards the end of 2014, the construction of a new 142-bedroom hotel, with meeting, banqueting and conference facilities, will also be completed at the site, which will increase the efficiency of the heating scheme further still.
The Doubletree by Hilton hotel will derive all its heating and hot water, as well as its cooling, from the open water heat pump installation. Heat recovered from cooling the individual hotel rooms will be reclaimed and returned to the community system to support the heating and hot water demand for the whole site.
Mike Spenser-Morris believes the scheme paves the way for other developments taking place near an open body of water, to benefit from this highly energy efficient system, doing away with the need for traditional combustion boilers, with their attendant carbon emissions.
“This open water heat pump system will be capable of producing over two megawatts of thermal energy for this development and will provide it 24/7, 365 days a year regardless of the weather or air temperature, even in the depths of winter,” he explains. “Almost every major city in this country is close to a river, lake, reservoir, canal or the sea.
“Every litre of water naturally stores, with the greatest efficiency, the valuable energy the sun delivers to earth each day,” adds Spenser-Morris. “There will be thousands of homes and businesses that can benefit from this most energy-efficient technology and in the process prevent thousands, even millions of tons of harmful carbon being released into the atmosphere from now on”.
Praising the drive of Spenser-Morris, who first acquired the development site in 1999, Ed Davey MP was also mindful of the potential that heat pump systems like this can offer the UK.
“This is the first installation anywhere of its kind in the country and it highlights what can be achieved when you have the vision and determination to champion such a new low carbon alternative to traditional forms of heating,” he said.
“I know Mike had to go all the way to Japan to find a similar scheme in operation, and also worked tirelessly with Kingston Council, his consultants and contractors, the Environment Agency and the heat pump manufacturer to realise his vision.”
Kingston Heights / River walk – the facts and figures:
• The community heating system uses Ecodan heat pump technology from Mitsubishi Electric to upgrade sensible heat from the Thames and deliver consistent heating and hot water to the apartments.
• The system will generate approximately 2.3 MW of heat output annually.
• An average of 150 litres per second will be abstracted from, and returned to, the Thames. This equates to 13 million litres per day and is the equivalent of five Olympic-sized swimming pools per day.
• The Thames flow rate is 260,000 litres per second so the system is abstracting a maximum of 0.05% of the available water in the river, and returning it immediately.
• The change in temperature of the 150 litres per second is at most only 3 degrees – a difference that would be assimilated almost immediately.
• A two-stage system of state-of-the-art filtration has been installed to ensure that no fish fry or other marine life can enter the system.
• Mike Spenser-Morris appointed White Associates as his Sustainable Energy consultants for the system development.
• Specialist contractor and developer United House Ltd was contracted to build and manage the project.
• The construction project included the technically challenging encapsulation of a live UK Power Networks substation within a steel-lined concrete ‘box’ 200 metres long, 38 metres wide and four storeys high.
• Christopher Smith Associates were appointed by NHP Leisure Developments as quantity surveyors and project managers for the project.
• Paul Brookes Architects were the architects responsible for the design of Kingston Heights and KDS Associates were appointed as project delivery architects.
Mitsubishi Electric
