DHL London Gateway – Commercial Solar Water Heater System
DHL Supply Chain has its own purpose-built depot, ‘London Thames Gateway’, a newly designed world-class distribution centre incorporating Lochinvar Commercial Solar Water Heating.
The decision to come to London Gateway represents a major milestone in their strategy to combine value-added and management services with traditional fulfilment and distribution. Located at the heart of London Gateway’s Logistics Park, offering direct access to the United Kingdom’s most connected trade hub. With advanced port and rail terminals on site, Logistics Park occupants become part of a multimodal supply chain that is faster, cheaper and more sustainable.
DHL’s significant investment in automation underpins its commitment to this strategic location.
They will benefit from the right location, the right infrastructure and the right technology to serve Greater London and the South East over the long term. The perfect choice to save time and instil a level of resilience within their supply chain – offering direct access to the United Kingdom’s most connected trade hub.
The new state of the art facility will be fully operational spring 2023, with Mars UK already committed to occupying 60% of the site.
When complete, the new facility will bring huge opportunities to the market, with a 42m high bay warehouse accredited as ‘outstanding’ by the leading construction sustainability standard BREEAM, an internal volume equivalent to 645 Olympic swimming pools, and market-leading levels of automation which will generate cost and time savings.
Jim Hartshorne, Managing Director, Retail & Consumer UK & I, DHL Supply Chain said: “It’s a really exciting day to see the official commencement of a landmark project such as this. We’re incredibly proud to be able to offer our customers operations that are not only world class in efficiency, but also exemplars of sustainable warehousing.”
Tim Walker, Supply Chain Director, Mars UK added: “This is an exciting milestone for our business as we look to realise our ambition of creating a truly world class logistics operation that is sustainable, smart and agile. What is good for our business is also good for the planet and this project is a meaningful step in our sustainability journey as we look to create the world we want tomorrow – which we know starts with how we do business today.”
The new site is one of two new warehouses under construction, the other located in the East Midlands. Representing an investment of £350m, the two sites will reduce Mars’ outbound logistics carbon footprint in the UK by 7.7%. The buildings themselves will be partially Solar-Powered and rated in the top 1% of non-domestic buildings in the UK environmentally.
The Solar Water Heating System
- 6 x LSP20+ Premium Commercial flat plate thermal panels
- The panels are feeding into 2x 388ltr twin coil vessels
- Total solar storage volume is 300ltrs – so 50ltrs per panel.
- Daily hot water usage is estimated around 2000ltrs per day
Solar radiation, direct and diffused is absorbed at the collector and converted to heat. This is transferred to the heat transfer medium (glycol antifreeze fluid with corrosion inhibitors). The sun is a variable power supply available only during the day and then in varying strengths dependant on the orientation and pitch of the collectors, time of day, cloud cover and season. The greater the suns intensity the higher the performance of the solar system will be. On days of low solar radiation the output from the solar collectors will be lower providing less energy to the solar cylinder.
The system is controlled by the DeltasolBX Differential Controller, this constantly measures the temperature within the solar collectors and the solar thermal store using sensors in the end of the solar array on the hot flow and the bottom half of the solar vessel.
When there is a sufficient ∆T between the collectors and the cylinder (6oc), the solar controller switches on the pump and energy is transferred to the solar vessel via the solar coil. Having given its energy to the solar cylinder the heat transfer liquid is pumped back to the solar collector for re-heating.
When the cylinder reaches its set point (65°C) or the ∆T between the collectors and the vessel drops to 4°C the solar pump is switched off. If the collector temperature reached the collector limit temperature (130°C) again the solar pump is switched off to prevent steam from circulating within the solar pipework. At this point the system will go into stagnation but the system will stay hydraulically secure.
For safety reasons the solar system has a high limit manual reset stat fitted at high level in the solar vessel, if activated the solar pump will have its power interrupted thus prevent further heat transfer to the solar vessel via the solar coil. The high limit stat is set to switch at 80°C
The solar array has been sized according to DHW use and the solar vessel size. The system is designed to heat the solar vessel efficiently without regularly going into stagnation. Stagnation will reduce the working life of the solar components and especially the heat transfer fluid.
If a fault occurs with the solar thermal system the Deltasol BX controller will begin to flash red. The AM1 alarm module will also flash red and send a signal back to the BMS.
