TAKING A CLOSER LOOK AT HYBRIDS AND BIOMASS

The market for renewable energy based heating systems has been clearly defined as one for people who are off the mains gas grid or understand that new build properties (mainly self –builds) can benefit the most.

For the twenty two million homes on the gas grid, what are the options, given that the majority of these properties are old and harder to heat than new builds? Gas prices, despite their volatility, are still relatively low and for those on the grid it is hard to justify the higher cost of a renewable energy based solution – such as a high temperature heat pump or biomass boiler – that is suitable for the property.

Heat pump and boiler manufacturers understand this and are now developing and marketing a new “hybrid” alternative. The Department for Energy and Climate Change (DECC) has researched this market and sees strong potential for hybrid, given that the fossil fuel boiler market is not likely to decline any time soon. This is good news as it provides a fresh alternative to the other two camps of fuel only or renewable only installations.

By widening the renewable market, hybrids offer greater choice and flexibility. A major benefit is that they will help us to reduce running costs and carbon emissions, whilst allowing us to revert to fossil fuels to power us through the worst of the UK winter months.

A hybrid system offers good economies as the system is set up to understand the cost of the energy tariffs and it decides if it should run on mains gas (or oil & LPG) or its heat pump. With rising gas prices, the economics then favour the heat pump as the gap between the cost of electricity and gas widens as gas prices increase. The UK climate actually will allow the use of the heat pump for between 60-75% of the heating season. Some systems also allow boiler or heat pump only modes, as well as parallel running.

For most UK homes space is often important and something that more traditional renewables based systems fall foul of. Vendors’ offerings vary – some have fully integrated solutions combining the fuel boiler and heat pump indoor unit, whilst others have separates. Combination boiler models are ideal for space limited installations.
So the UK renewables market finally has a middle ground solution to meet our growing energy and CO2 emission challenges.

Meanwhile in the field of renewables only, biomass tariffs (under the Renewable Heat Incentive, RHI) are available to both commercial and domestic users, Wood pellet boilers are attracting interest from all sectors of the market including homeowners and commercial users. For the domestic RHI scheme, homeowners can claim over seven years with tariffs designed to account for twenty years of heating. The domestic tariff has been set at 12.2 p/kWh. The payment will be based on the heating requirement as defined by a Green Deal approved home energy assessment as documented in the resulting Energy Performance Certificate (EPC).

Installers offering their services need to comply with the Microgeneration Certification Scheme (MCS) for all installations up to 70kW of capacity. For commercial installations additional rules apply for more complex installations. Having understood the financial incentives on offer to migrate from fossil fuel based boilers, the installer should explain to the customer some of the requirements of operating a wood pellet boiler. Firstly there will be similar requirements for the provision of an approved flue system. This is no different to any device that requires combustion for its operation. The need to store the pellets is also no more onerous than locating a bulk storage tank for heating oil or LPG.

Care should be taken however with the distance of the pellet store and how it is located in relation to the boiler. Ventilation is a consideration as wood pellets must not become damp and give off carbon monoxide when stored in bulk. Today’s modern pellet boilers offer user friendly and low maintenance features such as self-loading, self-lighting and self-cleaning. On balance the case for wood pellet boilers under the RHI schemes make this form of heating most compelling.

For more information, contact IBD, Unit B3, Forelle Centre, 30 Black Moor Road, Ebblake Industrial Estate, Verwood, Dorset, BH31 6BB, Tel: +44 (0) 1202 825682, Fax: +44 (0) 1202 820645, Email: sales@ibd-distribution.com www.ibd-distribution.com