Mr. Kevin O'Rourke:

Radiant heat in general is a more comfortable form of heat than, say, convective heat. Traditionally, we had electric storage heaters, which have been a mixture of both, as have what we call radiators. In fact, much of the heat given out by radiators is through convection.

The issue as regards the efficiency of infra-red heating is not the technical efficiency but the actual cost of electricity. Currently, people are paying about two and a half times as much for a unit of electricity at ordinary day rates as they do for a typical oil- or gas-fired system. That is the big barrier at the moment, but as we develop our electricity system, particularly with more renewables, and enter into a smart-grid environment in which we have more time-based tariffs, for example, the use of electricity for heating becomes a real option. It also helps as a demand balance to counteract the variability of renewables, but that is a bigger issue. In principle it can have a role to play in that environment, but if the Deputy is asking about the technical efficiency of infra-red heating as against electrical heating of any kind, it has that challenge to meet.

In fact, night-rate electricity is really what must apply in terms of electricity being economical at current rates.

With regard to the efficiency levels of boilers, it is now mandatory under the building regulations for new homes to install highly efficient boilers. They are over 90% efficient. A traditional oil or gas-fired boiler in an older house has an efficiency rate of between 65% and 70% approximately. A solid-fuel back boiler is between 35% and 50% efficient, and an open fire is approximately 20% efficient. That is the scale of variation.