The Isle of Wight experiences an excess of solar power generation in peak summer periods, with insufficient electricity demand to absorb that generation. The solar power is at peak generation during the summer months in the middle of the day, when demand for electricity is at its lowest – when everyone is out at the beach!
This project is working in partnership with award-winning, cleantech company Mixergy, to investigate whether it is possible to use the excess energy generated by the Homestead solar farm in Shalfleet to heat and store water in some of the Isle of Wight’s holiday accommodation using their pioneering internet-connected hot water tanks. This system will be able to off-set the heating of the tanks to low demand times during the day, and if connected to the appropriate energy tariff, could be using locally generated solar power to heat water and store it ready for use when required by visitors.
Together Mixergy and WCE devised a project to test the energy saving potential locked up within the hotel hot water systems on the Island. Specifically:
Is there an opportunity to lower energy consumption from the hotels hot water storage during peak and off-peak seasons?
- Is there much hot water usage variation between peak and off-peak tourist visitor season?
- Is there capacity within the Island’s hotel network to absorb excess solar PV energy generated during summer and use it to heat the hotels hot water cylinders?
At the beginning of the 2021 holiday season, Mixergy retrofitted their specialist software to hot water tanks at four hotels on the Island, to enable us to gather data on the hot water use patterns at each site. The software logs the hot water profile within the cylinder, detailing water temperatures, hot water level, heating times, heating periods and insulation efficiency. Each control panel is connected to the internet allowing 24/7 logging of this data. A report of these findings has been produced for each of the hotels, showing the results of the data, with suggestions for improving the energy efficiency of their current hot water system. Each site will be able to keep the Mixergy software and will receive a login to access their data to enable them to monitor their hot water use. This will give them opportunities to alter and fine-tune their heating controls to match the hot water use for each day to maximise energy efficiency and save money for their business.
The next phase of this project will fund the installation of up to three new Mixergy hot water tanks in these hotels, with a continuation of the monitoring of the hot water demand throughout the 2022 holiday season, to assess how the Mixergy tanks can improve the hot water supply and demand to save energy and save money on bills. The software attached to the Mixergy tanks will learn over time how much hot water is required during the day and will heat water to match the demand.
The project is already receiving positive feedback from the hotel owners:
‘’Just having the hot water level gauge has been a really useful tool, knowing when the hot water has got very low etc. When our tank got serviced in November the Mixergy equipment blew the engineer’s mind as he never knew this tech existed!’’ – Nick Clark, The Chestnuts, Shanklin