Nuffield Health's project to cut energy use and noise pollution has had its challenges. But 12 months, and savings of around £10,000 later, the effort was worth it.
Commended in the 2degrees Champions Awards 2015
Nuffield Health is a not-for-profit business aiming to make the nation healthier and is constantly exploring options to reduce their energy intake and environmental impact.
The wellbeing centre at Hertford was chosen as one of the sites to trial reclaiming energy from the Air Conditioning system that could be re-used for hot water production.
This site also had issues due to its proximity to local houses as the water chiller was originally installed with noise dampers, which on warm days caused the chiller to struggle to achieve its target temperature due to the restricted airflow through the condensers. This meant that in the summer the dampers often were left open, which in turn caused noise pollution for nearby houses.
The project had 4 objectives:
Reduce gas consumption;
Reduce electricity consumption;
Reduce environmental impact from the site; and
Reduce noise pollution for local housing.
What did we do
A bespoke Geyser Thermal heat recovery system chosen as the preferred solution.
The system was bespoke built to work with the existing plant and was designed to remove the available waste heat from the chiller. The water produced by the heat recovery system was at 64C, which was then used for the showers on site.
The heat recovery unit itself was bespoke built for the chiller on site and using automatic controls, reclaims otherwise wasted energy from the chiller, in effect increasing the condenser capacity by 20%. This reduces the load on the compressor and in turn the energy demand of the chiller, thus providing lower energy consumption from the chiller and considerable amounts of free hot water.
Since the Geyser heat recovery system is only recovering energy and not generating it, very little energy input is required, in fact the system uses only 60w/hr.
The trial was very successful and the results speak for themselves.
After 12 months of operating, the heat recovery system proved itself by:
Reducing gas consumption by the boilers by 127,680 Kwh;
Reducing electrical consumption by the chiller by 42,000Kwh (just under 10%)
Reducing carbon emissions by 45,44 tons;
Removing the need for the dampers to be opened in the summer - no more noise pollution nor complaints.
On average, every day of year the site is getting over 5,000 litres of hot water for free and at the same time using 115Kw/hr less electricity. (This is enough energy to make over 22,000 cups of tea every day (teabags not included.))
In financial terms the installation is saving £ 9,600 per annum, not include any savings from reduced carbon taxes, providing a payback of only 2 years.
On average the 60 watts used to run the circulation pump saved 14.58 Kwh, 24/7/365.
The personal pitch
In the last few years much focus has been on governmental incentives to use renewable sources for generating energy. Refrigeration systems can be one of the highest costs for many businesses and it also contributes considerably to global warming.
This project has shown that there are technologies out there that can increase efficiencies, reduce carbon emissions and save energy without the need for governmental funds to make it financially viable. The 2 year payback achieved on this project is purely from improved energy usage within the site.
This retro fitted system at Nuffield Health is in effect using the energy from members whilst they are exercising to heat the water the members use for their own showers and at the same time reducing the demand on the grid.
Suppliers, contractors and solutions providers used
Lolli Olafsson, Geyser Thermal Energy Ltd
Colin Ellinor, First In Service, CEllinor@firstinservice.co.uk. He was in charge of the installation itself.