Ground Sun installed a water source heat pump system for this beautiful riverside cottage in Hertfordshire.
Two Ochsner GMSW 7 plus heat pumps were installed in cascade to provide 100% of the space heating and hot water requirement of this 200m2 property.
A cascade system is the most efficient method of installing heat pumps as designing heat pumps for the peak load in one unit means the machines are oversized in normal operating conditions for the majority of the year. The Ochsner controllers share out the running hours between the two heat pumps and also ensures a backup is always available.
The system was installed as an open loop system where water is extracted from the river and filtered through a 300-micron pump screen with backwash to ensure only clean water is pumped to a heat exchanger in the nearby plant room. The heat pump cools this water by circa 1.50C, extracts this energy and transfers this to the heat pump where it is converted/enhanced to provide 450C water for the heat emitters (underfloor heating and radiators) and hot water at 600.
Previously this house was heated by LPG tanks which had to be carried over a footbridge – this was both an inconvenient and expensive method to heat the house.
The installation is eligible to quarterly payments from the RHI (Renewable Heat Incentive) Scheme for a 7-year period and the system should achieve payback within 5 years.
100% of all this property’s heating and hot water is now from a renewable source giving a circa 80% reduction in running costs.
Our client would recommend that anyone with a property beside a body of water should consider this technology and has indicated he would be happy to discuss the benefits of this scheme. Please contact Ground Sun if this is of interest.