- Excess heat groundwater modelling part of £10bn Transport for London project
Ground source heat is rapidly catching on as a more sustainable alternative for the heating (and cooling) of large developments. At the current time, aquifers can be readily exploited for net extraction or disposal of heat, but as the number of developments using this technology increases, so the number of heat sources and sinks in an aquifer will increase. Where a dense concentration of such systems is being used, the groundwater abstraction wells used may start to abstract water which has already been warmed or cooled, reducing their efficiency. Whilst there is no current or upcoming legislation to regulate this, it is most important for industry to regulate itself to avoid these problems.
ESI is working closely with Parson Brinkerhoff, one of the partners working with TfL on the Cooling the Tube Programme, having secured a contract to provide a prediction of potential interference effects of the proposed ground source cooling systems . This is something which requires an in-depth knowledge of both water flow and heat transport in an aquifer, in which ESI excels
TfL is investing £150m of its £10 billion programme to address the issue of heat on the Tube. Getting heat out of the London Underground (LU) network is a huge engineering challenge. TfL has established a dedicated programme team to provide solutions to prevent temperatures on deepest parts of the network rising to unacceptable levels. The need to avoid increasing temperatures on the Underground system is actually the flipside of TfL’s success. Services are planned to increase by 25%, and new trains, that can accelerate quicker, are on order. But moving more customers and more trains takes more energy, even when the best of modern technology is applied, and more energy creates more heat.
And, controlling temperatures is harder than ever before, because the ground around the tunnels has heated up over the many years since they were built.
Keeping the Tube’s customers cool involves developing new technologies, as well as making best use of more traditional approaches. And every effort is being made to ensure that “green” methods are used wherever practicable. The work of the Cooling the Tube Programme has already earned two prestigious awards for sustainability.
While many of the details are currently confidential, ESI, together with Parsons Brinkerhoff , will be presenting some key findings at a meeting at the Geological Society’s Burlington House, on Piccadilly, on the 3rd December 2007. For registration details of the Geological Society conference, ‘Hydrogeology in Heat Engineering’:
http://tinyurl.com/2gyquu
For Transport for London’s news release on the Tube cooling trials: http://tinyurl.com/yvn6dv |
