The Problem:
The heating was provided by two 100kW gas boilers which were over fifteen years old and had become unreliable and costly to maintain. The energy consumption was excessive and led to high running costs. As the client was keen to utilise renewable energy where possible, whilst still working within a budget,
several options were considered including biomass boilers. However, air source heat pumps were chosen in favour of biomass. This was due to the logistics of managing fuel deliveries and the on-site fuel storage required for a biomass system.
EOC Services' Solution:
To provide a renewable and cost effective solution to reduce energy costs and carbon emissions the two 100kW gas boilers were replaced with a bivalent heating system.
The bivalent system comprised an air source heat pump acting as the primary heat source, supplemented by a single 100kW gas boiler. This provided the client with the perfect balance between the utilisation of renewable energy and affordability.
In the bivalent system installed at the King Edward VII Sports Hall the Daikin Altherma Flex heat pump acts as the primary heat source and a new 100kW gas boiler acts as the supplementary heat source. A Daikin EKCCW sequence controller was installed to seamlessly manage the control of both the heat pump and the boiler.
The heat pump is expected to meet all the heating requirements down to an outdoor ambient temperature of 70°. Once the temperature drops below this the sequence controller will run both the heat pump and boiler in parallel to meet the total heating load. It is estimated that for this project the heat pump will meet 70-75% of the annual heating demand with the remainder covered by the boiler.
Along with improved levels of comfort and lower fuel bills, the new owners will benefit from the new easy-to-use intelligent control unit, with a back-lit and plain text interface. As a result, day to day control is straightforward, while accurate feedback is provided on operational conditions and energy consumption.
eFutures Project
Prior to the installation of the new renewable energy heating system, the school was able to take part in the eFutures project which was a project partnership between the National Trust and Norfolk County Council. This is part of Norfolk County Council’s plan for delivering a 25% carbon reduction by 2014.
Selected pupils were able to contribute ideas to help improve the school environment and save energy during ‘The Big Switch’ energy saving week.
This was then followed by the formation of an action plan to achieve a target saving of 10% of the fuel bills when compared to the previous year.
The successful completion of this project enabled the school to secure £12,500 funding which was used towards the capital cost of the renewable heating installation.
Conclusion:
The Daikin Altherma Flex system, working alongside a traditional gas boiler aptly meets the demand for heating, with a reduction in ongoing energy bills and decreased carbon emissions.
The ongoing savings for energy and carbon emissions are predicted to be over 30%.
As far as I am aware this is the first project of its kind in the UK so it was quite exciting to be involved in this. I am particularly proud to have been given the opportunity to work on this project as there were several design hurdles to overcome. Alterations were made to the existing pipework to accommodate all the new plant, a steel frame was designed to enable stacking of the Altherma indoor units, a buffer vessel was required to ensure that all circulation pumps were not fighting with each other. A plate heat exchanger was also required to separate the heat supply circuit which is pressurised from the open vented heat emitter circuit.
Robert Hill, Technical Services Director at EOC Services
Our Satisfied Client’s Thoughts:
We chose the Daikin Altherma Flex system, after having gone to tender, as this provided us with the best value for money solution as well as decreasing our carbon emissions substantially.
The school’s Business Manager, Steward Bunting
Other Case Studies
