Without a doubt, the UK water heating market is going green with renewable options now on offer. One renewable solution is solar thermal water heating, and many manufacturers have recently introduced solar products. Heatrae Sadia launched its unvented Megatech and vented Megalife Solar cylinders last year, and sales figures have been very encouraging. Here, marketing manager David Webster explains the factors driving the solar market and gives specifiers, building managers and installers some advice on what to look out for when choosing a solar thermal cylinder
REDUCING the UK's carbon emissions is a hot topic, and businesses, public sector organisations and housing associations are finding themselves under increasing pressure to incorporate renewable, alternative energy solutions intheir new build and refurbishment schemes.
Renewable heating technologies extract and use the Earth's natural, free of charge, inexhaustible resources, reducing our dependence on the fossil fuels that are contributing to climate change.
The renewable technology currently proving most popular is solar thermal water heating. Solar systems utilise the most abundant energy source on the planet; they collect energy from the sun's rays and convert it directly into heat via collector panels or evacuated tubes positioned on a building's roof. This energy heats a liquid contained in the system's pipework, which is then circulated through a solar coil located in the base of a specially designed cylinder. This coil transfers heat to water stored in the cylinder - producing hot water.
Where domestic dwellings are concerned, running costs of a solar thermal system are thought to be up to 60% less than a conventional water heater, and they can save up to one tonne of CO2 per year*.
Currently, solar thermal systems require some form of supplementary water heating, provided via conventional gas, oil or electric boilers or electric immersion heaters. This is because, in the UK, the sun's energy can deliver only a proportion of our hot water requirements.
This proportion is, however, significant. In domestic properties it is thought to be about 50% year round but during the summer months solar energy can meet virtually all requirements**.
Solar thermal water heating has therefore become an increasingly popular choice for homeowners, local authorities and public sector and commercial organisations. Other new technologies can be used to provide water heating - ground source heat pumps, CHP and biomass for example - and interest in these continues to grow.
In addition to the carbon and energy cost savings solar systems provide, several factors are helping to grow the market; the main one being that it's now very accessible in terms of both information and product availability.
The majority of properties in the UK are suitable for solar technology, though this does depend on planning permission and the direction the building faces; ideally it should be south east to south west facing to obtain maximum benefit.
Solar thermal systems have received a lot of media interest, so most people have at least a basic understanding of how they work. The vast majority of people will also be able to comprehend the concept behind them. We have after all been using solar powered products for decades.
There is also a wide range of solar cylinders and systems currently available so specifiers, building managers and installers have many options to choose from. However, there are several things to consider before selecting a product.
Specifiers should be aware that even though manufacturers might claim their cylinders are solar, not all of them can be officially classed as such. Clear Skies/Low Carbon Building Programme recommendations for solar thermal hot water storage cylinders state that a minimum 30% of the stored volume of hot water must be dedicated to solar energy in order for the cylinder to be classified as solar thermal.
True solar cylinders also have a dedicated solar heating coil, which offers maximum efficiency and heat output from the solar energy. For supplementary water heating, indirect solar cylinders should have a separate, secondary boiler coil and direct versions should incorporate an immersion heater.
Heatrae Sadia is one of the few water heating manufacturers to offer direct solar cylinders, and sales have been promising. The growth of all electric buildings is encouraging demand; the UK is rapidly moving towards new build apartments and, often located on brown field sites, they are typically all electric. Of course, with electric, meeting SAP ratings is key but this can be achieved by incorporating renewables like solar thermal water heating and carefully selecting building materials that maximise insulation.
Specifiers should also consider the support package offered by manufacturers before choosing a solar system. For example, is technical and service support provided? Is this nationwide? Does the manufacturer offer advice, assistance, design services and product guidance?
The manufacturer should also offer solar training - after all, the future of solar thermal water heating very much relies on installers being appropriately trained via accredited courses.
Since we launched our Megatech and Megalife Solar cylinders last year we've been encouraged by the level of demand. Our unvented Megatech and vented Megalife Solar can be used with either flat plate collector panels or evacuated tube systems. Both cylinders are available in 190, 210, 250 and 300 litre capacities, in direct and indirect versions.
Being manufactured from Duplex stainless steel and undergoing comprehensive post weld treatments, Megatech and Megalife Solar offer the same high quality and durability that installers have come to expect from our market leading Megaflo HE unvented cylinder, and are backed by a 25 year on site parts and labour guarantee. We offer an accredited solar training course through our sister company Baxi.
Without a doubt, the future of the heating industry lies in the development of new, alternative technologies. Renewable solutions like solar thermal water heating systems are really gaining momentum, and we expect them to be adopted by many organisations across the UK - helping to reduce carbon emissions and fuel costs.
* Manufacturer's statement
**Energy Saving Trust
T: 0845 600 7402