Solar hot water at Rothera - Antarctica
Generating hot water at the British Antarctic Survey bases is currently a carbon intensive exercise. The energy needed for a person to have a typical four minute shower produces approximately 1·8kg of CO2. This is the same as running a shower, via a gas boiler, in the UK for nearly 7 minutes using 70% more water.
So, when the hot water system in Admirals House started to fail we took the opportunity to integrate solar hot water into the design of the proposed replacement system. This will reduce the amount of Marine Gas Oil (diesel) we need to burn and thus reduce our carbon emissions.
The design uses thermally efficient heat pipes enclosed within evacuated tubes as the collector to harvest the sun's energy as well as a large thermal store to hold the thermal energy until it is needed. We have a similar system already installed at our Cambridge site.
The replacement system has been designed such that the new thermal store will be used in connection with the current boilers to supply temporary hot water to the building while the old system is replaced and the solar collectors are installed. This should minimise disruption to staff and will reduce the costs associated with a separate temporary system.
The design calculations show the new system should save 7·5 tonnes of CO2, 2000 litres of marine gas oil and just over £1000 in fuel costs per year. We will be installing computerised energy monitoring so we can accurately measure the real savings of the system over time from Cambridge.