DECC provides a monthly RHI statistical update, with detailed information on the capacity of the accredited systems, and the amount of heat that they have generated by type of technology and facility. Key findings from the past 2.5 years include:
- Biomass accounts for almost 100% of the installed capacity
- Biomass systems are run on average for 2350 hours per year, but with significant variations – smaller units (1000kW) operating for almost 3500 hours
- Commercial solar thermal panels are operating at 400kW per installed peak
- Education sector (232 installations) runs their units for 980 hours per year
Today, environmental management is a key requirement for professionals involved in the design, construction and management of any property. When looking at a new heating system, a range of things must be considered – the size of the building, number of people using the building and how they use it, its daily usage, and usage during busy or slack times – and that’s before even thinking about the different types of heating system that might be used, and its integration with the existing system!
The figures here raise some questions over the use of the heat systems and their efficiencies, with operation of the units for a limited time during winter periods. There have been various reports, and we have seen ourselves, a number of poorly installed heat systems. This is due to a lack of tools, coupled with insufficient knowledge and training to understand the technologies performance and how to communicate the subject – issues that have been reflected in other CBx events.
Common issues relate to oversizing of the heat system, poor design where heat runs become too long, removal of heat storage and meters through value engineering, poor and incomplete commissioning of the heat systems and poor operation of the units.
A lack of reliable data and information about the success of renewables and the RHI scheme itself is hampering the growth of these projects. Government and industry each have a role to play, and must effectively engage in providing a framework for people to use renewables.
Typically, the areas of highest priority relating to behaviours or processes are not targeted, but instead clients are seeking a ‘technology fix’. There is a converse relationship, whereby the most fashionable activities – such as certification and ‘technologies’ – are those that deliver the lowest returns. While this is to be expected, as implementation rarely matches aspiration, it reflects the challenges many organisations face to fully implement policies within their own business. Implementation of projects is improving, but there are still horror stories.
Typical projects include a building where a recently installed renewable heat system was massively over specified, providing around three times as much heat as was needed, with no metering or heat storage.
This type of problem is putting companies off investing in renewables, and taking advantage of government incentive schemes – even when the schemes seem very attractive.
The non-domestic RHI scheme is aimed at commercial and industrial buildings. Public sector and not-for-profit organisations such as hospital trusts, charities and schools can all apply. District heating schemes, where one large system serves multiple businesses or homes, are also eligible.
The RHI scheme makes regular payments to those who decide to generate energy for heat and hot water usage from renewable energy sources. The guaranteed payments are made for seven years for households, and 20 years for business properties and organisations, which must be based in England, Wales and Scotland.