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Air Source Heat Pump Presentation. Andrew Knill Monmouthshire County Council. What Made Us Consider Air Source Heat Pumps?. Increased Number Of Complaints From Tenants About Their Solid Fuel and Electric Storage Radiators Systems. Sharply Rising Cost Of Oil (Winter 2005) .
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Air Source Heat Pump Presentation Andrew Knill Monmouthshire County Council
What Made Us Consider Air Source Heat Pumps? • Increased Number Of Complaints From Tenants About Their Solid Fuel and Electric Storage Radiators Systems. • Sharply Rising Cost Of Oil (Winter 2005)
Solid Fuel Complaints • Older Tenants: Unable To Carry Coal and Ashes Quite Expensive To Run Home Help Often Required. • Younger Tenants: Unable To Control System. High Running Costs. Dirty To Operate. Danger To Children.
Electric Storage Radiator Complaints • Unable To Control: Too Hot In The Night and The Morning. No Heat Left By The Evening. • High Running Costs.
Monmouthshire County CouncilBreakdown of Heating Fuel TypesJanuary 2005Number Of PropertiesPercentageGas 3045 84Oil 58 2Solid Fuel 227 6Electric 310 9 3640 15%
Cae Capel, Great Oak, Near Raglan. • Small rural site of 6 two bedroom bungalows heated with modern slim-line electric storage radiators. • Properties were built with cavity wall insulation and the loft insulation had recently been upgraded. The windows and doors were single glazed with aluminium frames. • Tenants were all old aged pensioners and had been campaigning for an alternative form of heating for a long time. Their main complaint was the existing systems were expensive to run and the radiators ran out of heat by the evening.
The tenants wanted LPG or Oil Heating. The site layout meant that communal LPG or Oil storage tanks would have to be provided as there was insufficient room for individual tanks to be located in the gardens. The tenants request was turned down because of bad previous experiences with communal storage schemes. (mainly metering, fuel contamination and tanks running out of fuel)
After further consultation with the tenants it was agreed to provide them with a wet central heating system with radiators fuelled by Combined Electric Primary Storage Units. • The units chosen were the Gledhill Electomate 2000’s • The systems were to use Tariff 10 electricity. • The tenants were to be set up on the Easy Warm scheme to ensure their fuel bills were capped and affordable.
Enquiries were made to the electricity supplier over the capacity of the network in June 2005. • It took until October 2005 before a quotation was received. • The quotation was for the sum of £7,500 and specified a minimum lead in time of 3 Months as a new transformer would be required in the village. • The quotation was immediately withdrawn by the electricity supplier as they claimed they needed more information about the Combined Electric Primary Storage Unit.
The Dilemma • A major internal refurbishment program was due to commence on the site at the beginning of January 2006. The work was to include kitchen and bathroom refurbishment, new central heating systems and electrical rewiring. • It quickly became clear that we would be unable to upgrade the electricity supplies in time. • By coincidence we acquired a HeatKing Air Source Heat Pump Brochure which under different circumstances may have been set aside.
What caught our eye in the brochure was that even at an external temperature of -10 Deg C the coefficient of performance (COP) of the Heat Pump was 2 !!
Locations Of Heat Pumps • Must Be Located Outside • Bolted Securely To A Wall Or Concrete Base • Consider Effect On Circulation Routes • Allow Adequate Room For Air Flow And Maintenance • Take Into Consideration Noise From Unit (Provide screening etc. if necessary) • Provide Soak away Or Drain For Condensate • Avoid Long Pipe Runs (particularly external runs) To The Unit.
Approved installers, Installer Training • All of the Heat Pumps we have installed have been fitted by our own Corgi registered engineers. • The training requirements are relatively simple. We ran a 1 day installation training course for our engineers and supervising staff. • Our engineers are able to install the units and attend to minor faults but are not able to work on the refrigeration circuit. • Any faulty units are swapped over and returned to the manufacturer for repair. The manufacturer has provided us with a spare unit and provides a collection service.
Typical Installation Costs Of Air Source Heat Pump Systems (2 Bed Bungalow) • Heat pump £3500 • Radiators and pipework £1450 • Wiring & Controls CH & HW £550 • Hot Water Cylinder £750 • Builders Work £650 Total £6900
Grants • Currently there are no grants available for Air Source Heat Pumps. • VAT on the cost of the heat Pumps is 5% • We have however received a one off grant from the Welsh Assembly Government via the Home Energy Efficiency Scheme (HEES Wales) to extend our trial of Air Source Heat Pumps.
Estimated Comparison of Energy Requirements, Cae Capel * Electricity Costs SWALEC 2005
Estimated Running Costs Of Air Source Heat Pumps From Actual Meter Readings
Air Source Heat Pump Reliability • Fitted a total of 19 units since February 2006 • 3 Units failed to work on commissioning • 1 Unit broke down within 7 days of installation • 1 Unit broke down after 8 months running • Of the 9 units fitted since last January none have yet broken down, indicating that early reliability problems have been addressed We keep a spare unit in store which can be swapped over in a couple of hours. The faulty unit is then sent back to the manufacturer in Yorkshire for repair
Some Of The Advantages Of Air Source Heat Pumps Over Other Systems • Heat production is fully controllable • Can be used on standard 60A electricity supplies • No bulk storage of fuel is required • 50-75% of energy produced is renewable * • Sealed units mean no specialist knowledge required • Operation and Maintenance requirements are very low • Long life expectancy typically 20 years+ • Low water temperature reduces risk of burning
Some Of The Disadvantages Of Air Source Heat Pumps Over Other Systems • Installation costs are generally high • External units are noisy and require careful sighting • Capacity has to be very carefully matched to load • Output decreases as external temperature decreases • Radiator outputs need to be between 2-3 times greater • Unable to heat water and central heating at same time • Unable to fully heat hot water (efficiently) • System needs to be filled with expensive antifreeze
Schematic Diagram Of Central Heating Only Air Source Heat Pump Installation
Coefficient Of Performance • The coefficient of performance of a heat pump is the ratio of energy given out to the electrical energy put in. • For a heat pump with a COP of 3 you would expect to get 3KW out for every 1KW you put in. • 1 KW would come from electricity and 2KW would come from heat extracted from the air.