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Woodfuel Education and Marketing Case Study Evaluation of Woodburning Installations in Wales:
Summary.
The use of wood and other biomass to provide heat and energy and displace fossil fuels has been developing in Wales for a number of years, and there are now over 50 of the newer technology systems installed along with a large number of traditional wood stoves and boilers. The aim of this project was to determine how successful these newer installations have been in terms of the practicalities of establishing and running them as well as in terms of the contribution and cost effectiveness of displacing greenhouse gas emissions from fossil fuels. Other issues such as fuel availability, energy security, employment, business and community development were also considered. Note that the study is only intended to provide a snapshot evaluation of systems actually in use, and is not a comprehensive definitive study.
This project was carried out with the support of Interreg IIIC European funding (Robinwood) and in partnership with the Forderkreis Waldschule Eberswalde, Germany (the Lead Partner).
15 installations were selected that covered a wide range of outputs (8kW to 500kW heat projects plus one 1500MW coal/co-fired power station). (Information from 3 sites in Brandenburg was also collected but is not summarised here). A questionnaire and site visits were used to obtain the basic information which was then analysed. The results are as follows:
Outputs
Pre-installation:
In the early stages, information was hard to find, quotes hard to get.
Early on, information could be overly optimistic and misleading
Installation work could be problematic, particularly for the larger schemes.
Installation often took longer than expected.
Enthusiasm and tenacity often required to see a project through
Lowering CO2 emissions was the major driver in most of the cases studied.
Post installation
Mixed experience:
Some larger installations worked well but others had significant teething problems
Later, the clients tended to be pleased with the equipment and with the controls
A small number of boilers never worked well
Log stoves and boilers, and pellet stoves were relatively easy to install and use.
Fuel
Firewood
Bought logs can actually be more expensive than realised but are popular
This cost may be balanced by the potential of ‘free’ firewood from off-cuts or timber from the user’s property and elsewhere.
User input (chopping, carrying) often seen as positive
Potential for local suppliers
Briquettes expensive, and few suppliers
Chip
After early problems, chip supplies now tend to be of acceptable quality
A number of boilers can handle chips of up to 50+% moisture
Locally supplied, and potential for future development
Tended to be the cheapest fuel, especially if from own resource or timber co-products.
Pellets
Theoretically an ideal fuel, but quality has, at times, been a big problem
Continuity of supply has been a problem
Some bulk contracts have been under the equivalent oil price but small supplies can be more or much more expensive.
Outcomes
,b>Cost Effectiveness, in terms of heat cost (pence/kWh) and cost of fossil fuel CO2 displacement.
The latter is often stated as the reason for moving to biomass heating. As it is now becoming generally accepted that there is limited biomass resource in Wales relative to energy demand and that it is unlikely that unlimited subsidy will be available, the cost effectiveness of wood heating installations is important. (The effect of grant funding of projects - or Renewable Obligation Certificates for heat production - was ignored in our calculations)
The capital cost of biomass boilers tends to be 5 to 10 times greater than gas or oil boilers. With large schemes the extra cost can be diluted where there is a high total project cost of a new-build or re-fit (due, say, to an extensive heat distribution system). The high costs can also be absorbed where a scheme is supported by a large organisation (e.g. a county council) with high revenue throughput, and notionally spread over 15 or 20 years. With other schemes (domestic, small businesses) even with some subsidy, significant finance must be found up front and this must be a disincentive. Nevertheless, we spread the capital costs over the appliance lifetime for all cases studied.
The majority of schemes would not have gone ahead without subsidy.
For cost comparisons with a fossil fuel system, the benchmark was the back-up oil boiler in case 11. For smaller systems the capital cost would be higher.
There was considerable variation in total costs (fuel, running, capital) of heat and CO2 offsetting across the range of installations (between 3 – 7pence/kWh, [the oil boiler was 3.8p/kWh] 11 – 27p/kgCO2). One boiler that worked poorly and another that was not being used to its planned capacity were excluded from these figures.
Some chip systems were at the lower end and total costs were cheaper than the oil system in the long term, but no savings could be made with the rest.
It was encouraging that the least cost effective were only twice the cost of the oil installation, a differential that could be reduced by a moderate amount of grant subsidy and/or might be acceptable to those committed to reducing greenhouse gas emissions.
Some larger scale systems were more cost effective, and capital costs might be reduced if the low-load systems could be run for longer. In fact many installations were operating at very low load.
However, there was serious concern that in many cases costs were not always being accurately evaluated. There were very few heat meters installed, and this is the only reliable way to measure heat delivered by an installation. The stated weights of fuel
used might not be reliable, some systems had no running/maintenance costs quoted, and nobody mentioned interest costs, (eg loan interest or interest forgone on capital that otherwise could be invested) which in some cases might represent a considerable annual sum.
By far the most cost effective case appears to be the wood co-fired coal power station. This is because of its age, so the capital cost has now been written off, and because wood is displacing a high carbon fuel (coal) that is used comparatively wastefully (much heat is discarded). The large scale (50,000 tonnes wood per annum) represents significant CO2 displacement.
Job creation
Installers, project managers
Fuel suppliers
Other benefits
Reduced landfill and landfill costs
Some installations used to demonstrate wood heating
Woodland management
Recommendations
Establish a standard procedure of installation and post-installation monitoring with heat meters, accurate fuel recording, running experience and costs, to properly evaluate the operation of the installation, the capital and establishment costs.
Application of this monitoring procedure should be a requirement of any grant funding
More support and promotion of simpler and cheaper technology, e.g. efficient log-burning stoves and basic boilers that are more affordable to the small user who pays the capital cost up front. This also stimulates a local supply chain.
Could subsidy similar to the Carbon Trust’s no-interest loans for SMEs for renewable energy or energy efficiency be provided for the private smaller client?
Target large organisations with large heat demand, where the high cost can be better accommodated.
Put greater emphasis on exploring the co-firing/coal power station option where CO2 displacement can be very large but at low cost.
Improve the sources of objective technical and cost information
Consider, where appropriate, upgrading an old gas or oil installation to a highly efficient gas or oil boiler: the fuel saved could pay for the capital and installation cost in only a few years with up to 30% reduction in greenhouse gas emissions.
For further information please contact Andy Stewart at Coed Cymru, 01686 650777
(OR see Staff Page for email addresses and officers' telephone numbers).
Coed Cymru, The Old Sawmill,
Tregynon, Newtown,
Powys SY16 3PL
Tel 01686 650 777
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