How do you improve the thermal environment within a building this big?

Background

Our reputation as trouble-shooters in existing buildings led to this enquiry from the client’s estates team, individuals whom we have successfully worked with on several critical projects.

The two buildings are used to maintain and keep the latest 12 car trains in operation within the busy Thameslink network. The Three Bridges depot has the equivalent cubic capacity of 30 Olympic sized swimming pools!

The Brief

Since the buildings were handed over, the maintenance engineers have experienced elevated temperatures within the facility during the summer. This has led to the need to improve the thermal environment within peak summer periods and, at the same time, drive energy efficient improvements.

We were asked to consider options for the way forward, including the consideration of the ongoing operational requirements of the building and to minimise disruption.

Challenges

The challenges that we were to overcome included the following:

• 25kV OLE railway electrification at a high level within the sheds
• 24/7 maintenance operation within all lanes continuously
• the sheer scale of the buildings we are to improve
• Each of the lanes has 2.5 tonne overhead gantry cranes which run the full length of the track internally.
• The building is only 18 months old

Process

Through the benefits of using dynamic thermal modelling techniques and computerised fluid dynamics, we were able to simulate the existing conditions and then apply our options to move forward.

This feasibility included a detailed cost/benefit analysis that revealed that there could be significant improvements made to the existing central ventilation, and this option would present the least disruptive approach to the business. Taking into account life-cycle costs, it was also confirmed that this would be a more cost-effective way forward.

We obtained planning permission for both sites and tendered the works. During this process, we are engaged as principal designers under the Construction (Design and Management) Regulations 2015, and the designs are currently being installed to both sites (2019). As well as overseeing the technical aspects of the projects, we will soon be heavily involved in the commissioning process to ensure that the planned improvements are delivered and energy efficiency is maximised.

Outcome

Following the agreement of the best way forward, SVMA has taken on the design for both facilities. Once completed, the result of the whole process will result in the desired improvements to the thermal environment, thereby producing increased equipment efficiency and advancements in employee productivity, particularly during peak summer periods.

Additionally, as a result of the project assessment, we identified that 75kW/hr of energy could be saved at peak times by replacing the new general lighting with an LED upgrade. Siemens is now in the process of implementing our recommendations as a separate exercise. As this will substantially help reduce the thermal load to the facility, it will continue to improve the thermal environment further.