North Lanarkshire Council's (NLC) housing stock includes approximately 4300 apartments situated in multi-storey dwellings.
Following a detailed search of the nongas options by NLC, it choose the EHC Fusion electric boiler and the EHC combination radiators as the preferred heating systems for these apartment blocks. One factor in the decision was that EHC offer a full support programme to assist the tenants with a comprehensive education on the Economy 10 tariff and the operation of whichever new heating system choice the tenant made.

The initial installations commenced during June 2007 and to date five multi-storey blocks comprising of approximately 555 apartments have been satisfactorily completed. During a review which included NLC, Scottish & Southern (the suppliers of the Economy 10 electricity tariff) and EHC in December 2007, running costs to date were analysed and they appeared to be providing good value for money for the tenants.

In order to validate these results it was agreed to appoint an independent research company to undertake performance validation of the two domestic heating technologies. Alembic Research, a recognised authority in energy auditing, was commissioned by The Electric Heating Company to monitor the performance of the heating systems recently installed in 8 flats. The flats either had a Fusion Electric Boiler and wet central heating system or the Company's EHC Electric Combination Radiator system installed. For the purposes of the exercise it was decided that 4 dwellings with each system be monitored.

During the survey temperatures were recorded for every dwelling in the main living room, the bedrooms, the hallway, the kitchen and the bathroom. In addition the external air temperatures were recorded on the different sites on which the test houses were situated.

The results were very revealing. They indicated that the eight dwellings monitored experienced very different use of the electric heating systems: some of the dwellings making very extensive use of the systems and heating their homes to very comfortable standards, others using the heating minimally. This is reflected in the mean daily expenditures of the monitored households (averaged in Table 1 below), which range between £1.15 and £2.45 per day (the equivalent of between £8.05 and £17.15 per week). As this was a six months monitoring exercise, the estimated total household fuel bill for the full year costs would range between £419 and £892 (see Table1). The results show that 58.5% of the consumption occurred on the off peak rate of the E10 tariff with the remaining 41.5% on the peak rate.



Table 1: Summary results - all dwellings

Mean House Temperature is measured in degrees Celcius. Electricity Units are measured in kWh. Mean Unit Rate is p/kWh. *includes standing charge

Compared to the storage heating which was previously installed in these dwellings, the costs associated with using the two direct electric heating systems monitored are favourable. Total energy consumption and annual fuel costs, for the same standardised heating and temperature pattern assumptions, are set out in Table 2 (below) for the two direct electric systems using two different assumptions on the split of electricity consumption between day and low E10 tariff rates - 60% day / 40% low and 40% day / 60% low.

Table 2: Estimated Total Energy Consumption and Fuel Costs - all dwellings

The estimated energy consumption for all of the direct electrically heated dwellings is less than that estimated for a storage heating system, varying between 1.3% and 10.8%. The estimated fuel costs for the direct electric systems is dependent on when the fuel is consumed - the more that is used in the peak charging period, the more costly the fuel bill. Under the current split used within SAP for direct electric heating on an Economy 10 tariff (i.e. 60:40 split between the day and low rate), electric storage heating would appear to be the cheaper option for all of these households.

However, in reality the off peak: peak ratio found in these dwellings was 40:60 in favour of off peak and as such the direct electric systems were estimated to be generally cheaper than the storage heating systems. Of course, the ability to heat during a peak period (offered by the two EHC systems), creates the potential for a more comfortable temperature in the home, a facility not available with standard, offpeak storage radiators.

Individual room temperatures varied. Overall, the heating systems demonstrate that they are able to cope with cold weather, as they achieved 20oC and much more, when the external temperature was below 0oC.

Due to the positive results of this monitoring exercise, EHC believes that their Fusion electric boiler or EHC electric combination radiators offer social housing landlords and their tenants the best value for money in non-gas areas.

For more information or a copy of the full report please contact The Electric Heating Company on 01698 820533 or visit www.electric-heatingcompany.co.uk