The HARP database allows Building Energy Rating assessors to enter real performance data for heating appliances when calculating Building Energy Ratings rather than low default scores - but few renewable appliances are listed, and the industry appears confused and deterred by the application process. Lenny Antonelli investigates.

Listing the estimated seasonal efficiencies of technologies including gas, oil and biomass boilers, solar thermal panels, heat pumps and CHP units, HARP (Home-heating appliance register of performance) is Sustainable Energy Ireland's database of household heating appliances. If an appliance is listed on HARP, its certified performance figures can be used when calculating Building Energy Ratings rather than conservative default values, which often drive ratings down.

Clearly it's in the interest of manufacturers and suppliers to have their appliances listed - doing so makes BER-conscious builders and architects more likely to specify them over unlisted appliances for which low default scores must be entered. But at the time of going to print, there were just three heat pumps, ten solid fuel boilers (including seven pellet and two log boilers) and thirteen solar panels on HARP compared to 3,043 gas, oil and LPG boilers. Speaking to Construct Ireland, various industry figures said the requirements for getting listed are impractical and overly stringent, while there also appears to be confusion regarding SEI's application requirements.

SEI told Construct Ireland that HARP applicants must submit certified test performance data that has been accepted by an accredited body along with an application form and photographs of the appliance. This seems straightforward, but various industry figures said that in practice getting listed is difficult.

"I recall spending quite a bit of time trying to go through the form and it was extremely tedious, and in the end I decided the day was too short to get through the procedures," said Paul Sikora, former MD of the now defunct Irish heat pump manufacturer Dunstar.

High standards are clearly important, and some form of independent certification is necessary if performance data is to be used when calculating BERs. However, with so few renewable appliances on HARP, it's obvious sections of the industry aren't engaging - or are struggling to engage - with the application process.

The requirements for getting listed are essentially the same for gas and oil boilers as for other appliances, but many models in this category were automatically transferred to HARP from SEDBUK, the UK's boiler efficiency database.

The HARP database is administered by Gastec, the UK company that also processes applications for SEDBUK. Construct Ireland contacted Gastec, but the company directed questions to SEI. One industry figure told Construct Ireland that in his experience, SEI were generally willing to accept performance data and certification provided Gastec did.

With the actual efficiency figures of many common gas and oil boilers readily available to BER assessors - and the seasonal efficiencies of many renewables not - there's a danger the market for these technologies could be depressed as builders and architects look to boost BERs by selecting HARP-listed oil and gas appliances instead.

One story relayed to Construct Ireland by Mike Teahan of heat pump supplier HSB demonstrates this. Teahan said that a developer his company supplied 5kW heat pumps to for a mid-sized residential development almost opted for gas boilers instead, as HSB was unable to get the unit's performance data accepted based on certified results for the equivalent 8kW device. Ultimately the BRE - the UK's Building Research Establishment - were engaged to separately certify the 5kW machine. Various industry figures that Construct Ireland spoke to said that, in a line of heat pumps that are essentially the same apart from the size, the difference in COP is unlikely to vary by more than 0.1.

So what are the main difficulties regarding HARP within the industry? Speaking to Construct Ireland, industry figures said SEI's application requirements make it difficult for appliances to be self-certified by manufacturers. Self-certification enables manufacturers to test the performance of their own appliances, and can be an effective way of enabling the industry to demonstrate the efficiency of its products without imposing excess cost and administration - provided the process is independently audited and monitored to verify results.