Alternative energy has to move from being an interesting technical sideshow into the mainstream of the heating industry. John Haven reports
Many people are unaware that space and water heating in the UK accounts for 44% of all the nation’s energy use. Transport, by comparison, accounts for 35%. According to many commentators, the discussion is over.
Clearly the contribution of our heating-based sectors significantly contributes to the UK’s share of global warming. Of course, then there is the increasing cost of fossil fuels, driven by the fact that the UK has changed from being a producer to a buyer of gas. In the past five years, the real cost of gas to the consumer has risen by around 40%, after decades of falling in real terms.
As a result of the very real barriers to cost-effective energy purchasing, heating manufacturers have had to act. This month, More Than Heat was launched – an initiative from Viessmann UK, which aims to promote the take-up of alternative energy in Britain.
UK barriers to alternative heating
Managing Director Stewart Purchase explained that there are significant barriers to the UK heating industry making a successful transition to alternative systems. “Just compare alternative energy systems with present domestic and commercial heating,” he said. “In today’s heating market there is a well established chain of knowledge. If a specifier calls for a certain type of heating system, he knows what it will give the customer and can be pretty sure that it will end up giving the designed performance.”
According to Purchase, this is not the case for alternative energy. “There are pockets of knowledge about particular systems but there is no chain of skill and experience remotely approaching that supporting conventional systems.” It is hoped that it is this series of gaps that initiatives such as More Than Heat will overcome.
“Alternative energy systems are different from conventional heating in that they are not ‘one size fits all’,” added Purchase. “There needs to be a clear understanding of what each system can and cannot do and how to apply it.”
There are technical issues too. For example a solar system can have fluid temperatures up to 250°C and pressures up to 6bar; twice that of a pressurised heating system, so that design and installation needs to recognise the safety issues.
The idea behind More than Heat’s package is to offer four key components to support a project from idea through to successful operation. These include:
u Training, both in the classroom and on site for installation engineers
The key to Viessmann’s approach is the width of products being offered – from conventional boilers through to alternative energy, enabling them to suggest ways in which systems can be integrated. For example, solar heating can be combined with condensing boilers to achieve the maximum benefit from both.
Typical of a project where this approach has been taken is the Y Gorlan School, in the Rhondda, Wales. In operation since May 2003 and serving 100 nursery, reception and pre-school children with a pre-school area which is open all weekdays of the year.
A total of 10m2 of vacuum solar tubes were used and these linked to a Vitocell 500 litre twin coil storage cylinder. The cylinder was also connected to a Vitodens 200 (60kW) wall-mounted condensing boiler. The boiler also provided central heating via an under-floor system.
After one year’s running, the total running costs were audited. These equated to 139kWh/m2 for the 620m2 building. This compares with a Chartered Institute of Building Services Engineers (CIBSE) energy audits yardstick (AM 5) for nursery schools (using the ‘good’ category) of 370kWh/m2 – a reduction of two thirds.