Over the last few years heating engineers, specifiers and manufacturers have learned a great deal about the use of solar-thermal technology to produce domestic hot water for buildings and are now highly experienced in the area. Simon Russell looks at how to get the best out of a solar-thermal DHW system.

The most cost-effective reductions in carbon-dioxide emissions form biomass boilers is best achieved by supporting them with condensing boilers. Chris Miles and Stefan Gautsch explain why they are the perfect partnership.

Monitoring of an installation of a Mitsubishi Electric Ecodan air-source heat pump in Hertfordshire has shown that it achieved an overall COP of 3.0 during December 2010, when the country faced long-periods of sub-zero temperatures. The trial shows that air-source heat pumps will work effectively under such harsh conditions and also highlights the importance of selecting rad­iators and heat emitters properly and ensuring that homeowners do know how to get the best from their system.

1125 MWh of electricity are expected to be produced each year by a 1.16 MW solar-PV installation in Somerset. The system was designed and installed by Solar SW using modules from A-Sun. Some of the panels are roof mounted, with the rest on the ground. Much of the electricity generated will be used on site, with the excess exported to the grid. The installation is expect to save 550 t of CO2 a year.

MHS Boilers has introduced a flat-panel solar-thermal collector that can be installed in the roof, on the roof or in a frame. The Solartron S2.5 from Elco has been designed to be very easy to install using only a cordless screwdriver, hammer and tape measure. These panels are available as horizontal and vertical hydraulically optimised versions, and each orientation is supplied with matching mounting systems and roof flashings. Collector fields can be created from multiple panels.

Heat pumps can deliver renewable energy 24/7, and there are few heating and cooling applications that cannot benefit from this technology. And with the Renewable Heat Incentive about to come into effect, the market is poised to grow faster than ever. Terry Seward puts heat pumps into context.

Between micro-installations and large-scale renewables are community-scale projects — with huge potential to help exploit renewable energy. Gambi Chiang explains how contract energy management can help develop this sector.

Andrews Water Heaters and Potterton Commercial, both part of Baxi Commercial Division, offer an extensive range of LZC (low- to zero-carbon) products that can be integrated with more tradition plant-room equipment such as direct-fire water heaters and boilers to reduce running costs and carbon emissions for commercial buildings.

Hoval has marked the upgrading of its training centre at the Centre of Renewable Energy (CORE) in Nottinghamshire with an open day for students from Nottingham University Faculty of Engineering. 12 students visited the facility for a presentation and discussion with Hoval’s renewables experts followed by hands-on examination of fully functional heat pumps, solar-thermal systems, biomass boilers, photo-voltaic system and wind turbine installed at the centre.

Visitors to The Building Centre in London can see in operation at SOLARflo solar-thermal water-heating system from Andrews Water Heaters. It is based on evacuated tubes, and visitors can see how much heat is being collected on a display in the permanent stand of Baxi Commercial Division in the showcase galleries.

Dimplex has added three new products to its solar-thermal water-heating range. They are a cost-effective plate collector, a high-performance evacuated-tube option and a single-branch pump station.

Mitsubishi Electric has expanded its commitment to renewable-energy technologies with the opening of a new training centre for renewable energy at its headquarters in Hatfield, Herts. The new centre enables the company to double the availability of training courses to 4000 a year. The company is also establishing long-term links with schools and colleges to fill the knowledge gap surrounding renewable technologies and capture the next generation of plumbing, heating, air-conditioning, air-conditioning and photo-voltaic installers.

Despite drastic cuts in the Feed-in Tariff, Andrew Lee sees huge opportunities for Solar-PV in the UK

Plumb Center is taking its renewables roadshow to six strategically selected locations during September. Visitors will have the opportunity to interact with dozens of exhibiting manu­facturers, merchants and professional bodies. There will also be four theatre areas providing demonstrations of domestic and non-domestic technologies, explanations of grants, legislation and regulations and also explanations of qualifications and providers.

Remeha has introduced an indirect solar-thermal water-heating system for homes that can meet up to 55% of the annual demand for domestic hot water and all of it in the Summer. The Sola system comprises insulated flat-plate panels for installing on the roof and a cylinder with a special coil in the bottom to transfer heat from the solar fluid to the water stored in the cylinder. The panels have a sealed low-iron glass cover to improve energy collection from ultra-violet and infra-red light, even on cloudy days.

Training organisation Logic Certification has launched a solar-PV designer course in response to growing demand from potential customers for solarPV but without the necessary experience to undertake the practical training. The course has been created for those requiring a fuller understanding of PV configuration and is intended for anyone involved in designing or managing solar-PV systems for others to install.

Vent-Axia has been accredited for the Microgeneration Certification for its Thernamic series of ground-source heat pumps by the British Board of Agrèment. They are therefore fully compliant with the technology requirements of the MCS and qualify for payments under the Renewable Heat Incentive, which requires the installer and the equipment to be MCS certified.

The launch by Dimplex of the EC Eau range of unvented water cylinders for heat pumps and solar-thermal enables the company to offer a complete solution for water heating using renewable energy. The range is made from 60% recycled materials and delivers mains-pressure hot water. A key design feature is the corrugated surface on the heat exchangers to maximise surface area and maintain a high usable volume of water.

Members of the Heating & Ventilating Contractors’ Association now have access to a tailor-made microgeneration certification scheme (MCS) for installers of renewable technologies. Thus benefit has been introduced as a result of a strategic alliance finalised by HVCA subsidiary Building Engineering Services Accreditation (BESCA) and independent certification body for the electrical industry NICEIC.

Paul Hardy argues that air-source heat pumps should be considered as part of hot-water generation in buildings, rather than just thinking of solar thermal

FETA’s Terry Seward brings you up to speed on the role of heat pumps as an effective means of exploiting renewable energy.

As part of its drive to reduce carbon emissions across its estate, the National Trust has replaced two oil-fired boilers at Sudbury Hall in Derbyshire with two 150 kW STU wood-pellet biomass boilers from Hoval. They were specified following a feasibility study by Lorien Engineering Solutions and visits to local Hoval installations.

Green Gate Mechanical Services is promoting its ability to offer a full design-and-build service for renewable energies throughout the UK on its new web site. Russell Warren of Green Gate says that the company has recently expanded its renewable-energy department in recognition of growing demand in the building-services sectors.

Air- and ground-source heat pumps are now officially recognised as sources of renewable by the EU Directive on the Promotion of Renewable Energy Sources, following its publication in the Official Journal.

Marchweeke Farm in Devon has installed a water-supply system powered by wind and solar energy. The farm specialises in home-produced meats and poultry which are delivered direct to customers’ homes.

Nigel Blandford draws on 25 years’ experience in the biomass sector to offer practical advice on getting the best from biomass boilers. He is currently managing a £750 000 project to increase the uptake of biomass energy systems in the north west of England.

Calorex heat pumps have been installed, or are now being installed, in over 2400 homes throughout the UK. The saving in CO2 is significant, as sales director Tony Barnes explains: ‘At a conservative 3 t per year per house, that is over to 7000 t per year.’

The DHW requirements of a school in Derbyshire are met by a combination of solar thermal and continuous-flow water heaters.

Solar energy is combined with oil to deliver domestic hot water for the new dormitory block at Brymore School of Rural Technology in Somerset. This school educates boys from 13 to 17 and differs from many other secondary schools by offering hands-on experience for learning through its organic working farm and gardens.

Azure Natural Energy Systems has notched up its second Heat Pump Award. The company, which is an approved installer of Dimplex heat pumps, won the installer of the year award, adding to its success last year as joint winner of the non-domestic installation of the year category.

Renewable energy is potentially inefficient. It is how you apply it that is the key to reducing carbon emissions, as Steve Cooper explains.

Heat-pump specialist Dimplex has welcomed the extension of phase 2 of the Low Carbon Buildings Programme until April 2011. An additional £45 million has been allocated to the LCBP, £35 million of which has been directed to phase 2 (the public-sector stream). The extension of the scheme will support the development of renewable technologies until the introduction of feed-in tariffs and the renewable-heat incentive.

Biomass boilers made by HDG in Germany are available in the UK through Euroheat. The range includes wood chip, shavings and pellet firing with outputs in single boilers up to 200 kW and the ability to be installed in modules.

Solar thermal is an accepted part of the micro-generation market — but how do you get the best from it? Paul Honeyman offers his advice.