Biomass degressions June 2015

The biomass degressions for both the non domestic and domestic Renewable Heat Incentive were announced at the start of June to come into force on the 1 July.

What has happened in June?

The first week of June was possibly our busiest ever week for selling wood pellet boilers to installers in Wales, Scotland and the North of England. This was mainly for the installer to be able to get the boiler in time to install it before the rate changes on 1 July.

Roger and Steve went out to Bulgaria early in June for annual training and an update on the NES product range. There will be some new log gasification boilers being added to the Pyroburn range as MCS accredited boilers. These will be affordable and without a Lambda sensor. 18, 25, 30 and 40kW.

There are many other upgrades, and we will release details when they become live.

Once back in the UK we attended the Eco Technology Show in Brighton. This was located at the Amex Stadium, home of Brighton and Hove Albion.

We exibited a 40kW wood pellet boiler (Pelleburn) with a 1500l thermal store. Perhaps our 2 best selling items. Fantasic weather over the week, finishing with a thunder storm on the way home.

At the show there were many interesting talks, and the panel discussion around meeting the 2020 targets for emissions reduction was the best attended. Caroline Lucas chaired the panel. One part of the discussion was that the RHI funding is to finish in 2017, and the total installations to date do not help the UK reach the targets for renewable heating without more funding. There is a new energy minister, Amber Rudd, who is yet to comment on the RHI, we will have to wait and see.

We were also near to the Center of Alternative Energy Stand. They have produced a document “Zero Carbon Britain, rethinking the future”, which I am busy reading at the moment. They do emphasise the need to improve the thermal quality of buildings and also point out that there are limits to “growing” biomass as there are competing demands for land. (Personally I do think that there can be better woodland management and co-ordination on a local scale to produce chip, pellet and log products. I also think that there will be substitute materials for biomass that can also be fuels. e.g. waste from anearobic digestion, recycled coffee granuals, straw, etc, all of which there is work towards meeting a standard at the moment). However the point is clear – if we want to reduce CO2 and CO emissions for heat then we are about 20% of the way there at the moment and 5 years to go.

After Brighton I went up to Scotland – firstly surveying a possible 160kW installation in Dumfries and Galloway with DMS Energy, after which of to Oban and Ferguson Energy, where I looked at a number of installations that had been running for some time, including the Bunkhouse on the Isle of Mull.

What struck me was, despite the rain, the area was beautiful and ideal for biomass. For homes the Pyroburn (log boiler), works very well as fuel can be plentiful.

What is the best way to get from Oban to Aboyne (near Aberdeen)? Up, underneath or through the Cairngorms? I went under and found the road shut (big detour), then on my return I went through and found the road shut (another detour), so perhaps the best route is above! I did, however, find Sugplumb Ltd very accomodating. They are also fitting a lot of renewables at the moment. I did notice the trees during my scenic drive!

After a brief pitstop in Blackford I went down to Oiline Ltd near to Colne, Skipton and Keithley. They have been installing mainly pellet boilers into an area that seems to be more rural than the Cairngorms. Certainly the roads are no better!

There do seem to be fewer trees in this part of North Yorkshire, however I do know that Oil Line are completing a Pyroburn log gasification boiler at the time of writing.

What remains of June for many is getting the RHI applications in before the deadline. We will be making further visits out to see boilers in early July.


Biomass boiler efficiency

Biomass boiler efficiency in general has come under some criticism in a recent Guardian article .

Key points from the Guardian article are that a DECC study of installed biomass systems found that the average efficiency of the boilers was 66.5%, that the surveyed systems can only reach 76% efficiency, and that this is lower than the needed 85% efficiency to contribute to carbon targets. Yet the original research also states  “In other words, the estimated central performance standards of 81.5% to 72% (and 76.75% on average) would only be slightly exceeded if the boiler were gas, oil or coal fired.”

Whilst the article was clearly pushing heat pumps, a rival renewable technology, there seems to be confusion in the text.

To qualify for the Renewable Heat Incentive biomass boilers have to conform to a European Standard EN303-5. In addition to this the boilers have to be tested to emit limited emissions.

The 85% efficiency relates to the EN303-5 standard and the class of boiler that can be used for an RHI Scheme. This is calculated in lab conditions from the burning of a specific fuel. This is not the overall efficiency of the heating system.

Over the last 2 years there are a number of variables that may have influenced the study.

Issue 1 – Heat Meters

Heat meters are used to measure effective heat that is used by the RHI biomass system. What is recorded on the heat meter is what is paid to the owner of the system. In the majority of cases the heat meters are placed on the entrance to the heated spaces. Thus they only measure what is being used, and not what is being wasted. In addition there have been some issues with the installation and accuracy of the meters, where the accuracy can vary by up to 30%. There are currently free courses to help remedy this.

Issue 2 – Fuel

When the RHI first came into being the boilers could be tested on a very efficient fuel, but in reality the boilers were using a similar fuel that was much less efficient.

For instance you can buy wood briquettes that can have a low moisture content e.g. 8%. These will burn very efficiently, in excess of 90% in the right conditions. However if you use logs that are not properly seasoned then the moisture content will be much higher e.g. 30%, and the efficiency of the burning process may be as low as 65%.

This issue has been addressed in part by a tightening of the specifications. However there are boilers installed that are burning poor quality fuel as it is cheaper than specified fuel. This is more prevalent with landowners or farmers. Today all newly installed boilers should only be burning specified fuel and the boilers should be able to burn with an efficiency of above 85%. Owners of the installation have to keep records of the fuel they have purchased.

Wood Pellets all have to be ENplus. Regular samples of pellets are taken and they are measured for moisture, dust (fines), hardness, and burn quality. There have been some issues with dust in particular. The pellets can degrade in transit and when loaded into a hopper. There are examples where the dust content can rise above 10 or 15%. Clearly this makes the efficiency of fuel to heat produced less efficient. Again these issues are often dealt with by an experienced installer, or many of the good distributors will offer replacement pellets if they have been wrongly handled. There are very few issues with bagged ENplus pellets.

The majority of the boilers in the study seemed to be using woodchip at 199kW. In the case studies provided the fuel used was often wood chips with a moisture value of 30 or 31 percent. Wood Chips are significantly cheaper than wood pellets, but burn less efficiencty, and therefore will have a poorer efficiency. For instance if the burn efficiency of 31% moist pellets is 80% then the heat transfer to water will be below 80%. This will largely explain the number of responses that seemed to be 70% + and fairly well installed.

Issue 3 – sizing of boilers

With Solar PV everyone who purchased wanted as much as possible. This produces more electricity, which is a good thing! For biomass the owner of a system gets paid the highest tariff up to 199kW. So if you are buying a biomass system for investment purposes then it seems that choosing 199kW will earn you more money.

The difficulty with this is that this causes 2 problems. a) The boiler is not run at its most efficient output. This is true, for instance, for many combination condensing boilers that have been sized for hot water production and not heating need. The boiler never reaches its optimum output and is less efficient as a consequence. b) The heat is not really needed. Here the owner is more interested in the tariff rather than the efficient distribution of the heat. The heat is then lost.

Issue 4 – UK weather and system management

UK weather presents a number of issues. Firstly we do have mild winters and cold winters. This can relate to the sizing issue. When you size a boiler you examine possible temperatures that you want the boiler to be able to cope with. For many this may be -3 degrees. In reality we may experience the majority of the winter with temperatures of between 6-12 degrees.

The other issue with UK weather is that it is intermittent. We generally do not need the heating on all day every day. Therefore you have to consider carefully when the heating needs to be turned on. If the following month is then warm you will wast the heat that is already in your system. For instance if you have buffer tanks and have spent time heating them up, only not to use the heat, then this heat could be lost and not used.

Issue 6 – General heating system efficiency

What is not clear from the Guardian article is how the efficiency is measured. The original article is far clearer and looks at the whole system efficiency rather than implying that the efficiency is all down to the boiler.

Before the heat gets to the heat meter there may be pipework (lagged), district heating pipe work, buffer tanks, and the transfer of the heat from the burn chamber within the boiler to hot water.

Examining the transfer from heat to water, there is a UK database that is slowly expanding that shows that heat to water efficiency (typically 80-86%) from biomass boilers rather than the burnt efficiency of the burning process that is often above 90%.

Due to the nature of the study being more about 199kW boilers for predominantly large retail systems with possibly wood chip boilers, it does not cover smaller systems that do not have district heating, or many pellet boilers.

If you are in doubt over what your system efficiency is or even means, then please get in touch with us.


What is biomass fuel – wood pellet boilers

Biomass boilers are well recognised, but what do they burn?

In the UK the introduction of the Renewable Heat Incentive has meant that the definition of biomass fuel has become more difficult to understand. The main driver for this are the emissions that the boilers have in addition to CO2 being of acceptable levels.

These limits are 30 grams per gigajoule (g/GJ) net heat input for particulate matter and 150g/GJ for NOx.

Each boiler range has to be tested with the fuel that is going to be used within it. Each fuel has a definition.

Wood Pellets

Pellets are the most straightforward for a homeowner as there is an ENPlus quality standard market on bagged pellets or on the website of the pellet producer.

http://www.enplus-pellets.eu/

All accredited wood pellet boilers have been tested to a European Standard EN303-5, met the standards of the UK Microgeneration Certification Scheme, and have a valid emissions certificate. Key to this is that the boilers were tested on ENplus pellets. So these are the only pellets that you can buy and use. To claim your RHI you will have to keep records and be able to show that you are burning ENplus pellets.

Wood Pellet Boiler Product Example

Pelleburn 15kW wood pellet boiler  will burn ENplus pellets only. When it does this it has been tested to show 9g/GJ for Particulate Matter and 81g/MJ for Nox. You can find a copy of the emissions certificate here. http://rhieclist.org.uk/wp-content/uploads/2014/04/NES_PLB_RHI.pdf

Wood logs

Logs are measured by moisture and by whether they are “virgin” or used. This potentially creates 4 categories.

Virgin timber – Very dry or kiln dried logs or logs with less than 25% moisture

Used timber – waste wood with no contaminants e.g. Pallets, or waste wood with contaminants e.g. MDF, Plywood, Chipboard

Wood Logs product Example

Pyroburn 30kW gasification boiler can burn wood with up to 25% as it was tested on wood with a moisture content of 12.01 percent. Had the wood in testing been much drier, e.g. 6% then there would be a limit of 12 percent dry wood in the boiler. http://rhieclist.org.uk/wp-content/uploads/2014/05/NES_PB_RHI.pdf

Wood burns much better and cleaner when the wood is dry. The testing process and regulations ensures that if you buy and use a log boiler you take care of what you put in it. For instance the following are attractive, but not allowable

  • Newly cut timber in excess of 25% moisture.  Fuel that you “find” in woods, or offcuts from timber merchants, or branches from a tree surgeon. This fuel will not burn well. You do not get the heat but your neighbours get the smoke.
  • MDF, Chip board or painted wood may burn, but it gives off lots of fumes. Unless there are very specific cleaning processes within the boiler to deal with paints and glues then the fumes produced will be toxic. This category of fuel (B2) cannot be burnt in the majority of boilers, and certainly no domestic or small boilers.

Logs can transformed into wood chip and sawdust and is subject to the same categories as above. Wood chip is generally quite bulky, so produced in local areas rather than pellets at one or two places. It varies in quality and next year (2015) suppliers will need to state that their fuel meets both a moisture standard and has no contaminants. We are excited about our new boiler The CB 160 which will shortly be released into the UK market.

Sawdust does not burn well and can cause back burning (fire can go back through the fuel delivery mechanism) boilers will specifically state whether they can burn sawdust or not. For instance the Catfire range of chip boilers can burn sawdust and has a mechanism to prevent backburning of sawdust.

Sawdust or shavings can also be made into briquettes easily (and pellets, but not so easily) that can burn very well and burn in most boilers.

As part of understanding the moisture content of the wood you would need to have an adequate storage and inspection process. For instance with pellets you need to check that there is not too much sawdust. For wood you will need to store so that the wood can mature. For chip you will need to keep it for a short period to ensure that it does not compost. Other than pellets, you will need to get a moisture meter to make sure that your wood is less than 25%.

Summary

If you want to install a biomass boiler you can only burn the fuel or fuels that it has been tested with. You will have to buy these fuels from accredited suppliers of biomass products from http://biomass-suppliers-list.service.gov.uk/find-a-fuel .

If you want to use your own stock of fuel you will have to self-certify and keep more detailed records. Again the fuel must relate exactly to the fuel tested on the boiler.

If you have questions about any of the above then please get in touch as we would be happy to help.


Energy from Waste – Sweden Leading Globally

Sweden has a problem. A rather unique problem.

They want to create energy from their trash, but their citizens are far too eco friendly to create enough trash.

They produce biomass and biogas from this waste, which is used as energy.

Each swede produces just over half a ton of household waste every year. Thanks to the efficient waste management in sweden, the vast majority of this household waste can be recovered or reused. Only four per cent is landfilled, which has lead to a rather interesting problem and solution.

Rather than simply producing more trash and recycling less, they have begun importing trash from other countries; roughly 800,000 tons annually. And what’s more, they’re getting paid to take it. Norway have started exporting their rubbish to Sweden, and Bulgaria, Romania, and Italy are set to follow suit.

Just over two million tons of household waste is treated from waste to energy in swedish plants every year. These plants incinerate a similar quantity of waste from industries as well. Waste incineration provides heat corresponding to the needs of 810,000 homes, around 20 per cent of all the district-heating produced. It also provides electricity corresponding to the needs of almost 250,000 homes.

Sweden is currently the global leader in recovering the energy in waste.

Energy from Waste. What an excellent idea.

Sweden has had strict standards limiting emissions from waste incineration since the mid-1980s. Most emissions have fallen by between 90 and 99 per cent since then thanks to ongoing technical development and better waste sorting.

Energy from waste is an environmental, financial, safe and stable contribution to the country’s energy supply.

Waste to energy is a recovery method that provides a significant part of Europe’s energy needs. One example of this is that around 50 million tons of waste are processed through incineration every year throughout europe. This corresponds to the heat requirements for the populations of Sweden, Norway, Iceland, Finland, Denmark, Estonia, Latvia and Lithuania.

In Sweden alone, waste incineration generates as much energy from waste to reduce carbon dioxide (Co2) emissions by 2.2 million tons per year. This is as much Co2 as 680,000 petrol-powered cars emit in a year.

Notice that the UK is left off the list of countries above, and that’s because we simply don’t create enough energy from waste yet.

Not in this particular sense at least.

There is another, popular, and domestic way to create energy from waste, and that’s with the use of a wood pellet boiler.

Wood pellets are manufactured from waste wood, such as off cuttings, and saw dust. It is then compressed and dried to create highly combustable and efficient heating fuel.

These pellets are added to a wood pellet boiler. They get transfered from the store to the boiler through the hopper, and are burned, just like you would burn any other fuel, to heat your home. This can be done on a home and industrial scale, and is financially rewarded by the renewable heat incentive.

So while the UK may be behind in creating energy from traditional landfill waste, we’re very much on the forefront when it comes to biomass, in the form of wood pellet boilers.

If you would like to know more about wood pellet boilers, this is a really thorough article for you to read.

And if you would like any more information, please contact us and we will be happy to help.


Log Burning Boilers or Wood Pellet Boilers?

If you are considering “biomass” as a heating system the most obvious choices are between log burning boilers and wood pellet boilers.

For some the clear advantages of log boilers are:

  1. Cost of installation
  2. Cost of fuel
  3. Sustainable use of wood

For others the clear advantages of pellets are:

  1. Automation of heating
  2. Higher efficiency
  3. Pellets are a waste product
  4. Space saving

Cost of Boiler

Log boilers such as the WBS active are MCS accredited and burn wood up to 90% efficiency. The boilers start at at a little over £1000 (20kW WBS) and this is a lot cheaper than the Pelleburn wood pellet boiler that starts at £3500.

Cost of Extra Water Heating

Wood pellet boilers modulate. This means that they can adjust to produce the  amount of hot water that you need to store for heating. Log boilers need to heat water when they are burning otherwise there is nowhere for the heat to go. This is often in the range of 30-50l per kW.

For instance a 20kW log boiler will need to heat 600-1000l of hot water.

You could choose an accumulation tank or a thermal store to do this.

An accumulation tank or “buffer store” can used to store the heat. They are well insulated and once heated can distribute the heat without the need for the boiler to be “on”. A 1000l buffer store is nearly 1 meter diameter by 2 meters tall. This does mean that you need to find space for this. The buffer store will be an extra £1000+ and there are extra plumbing costs in installation.

A thermal store can incorporate a hot water tank and heating hot water in one tank. A “tank in tank”. Assuming you need hot water for baths and showers, then you will need a hot water tank. Some houses already have these, some do not. Others are old and need replacing. A thermal store is a good solution if there is a need for a new hot water tank.

Wood pellet boilers do also benefit from the use of accumulation however they can burn efficiently for shorter periods of time and so need less water to heat. On smaller systems it is possible to work without one, however your boiler may need to come on more often. Using an accumulation tank may prolong the life of your parts.

In summary – log boilers need more accumulation than pellet boilers, and this will increase costs of installation. This will vary depending on the installation.

Space Needs

Wood pellet boilers that are completely automated generally infers a large pellet store that can be filled. This can take up a lot of space e.g. 10m3. This has to be dry and purpose built. Whilst there are pellet stores that can be outside for most homes the choice is between a top loading boiler (ie no storage) e.g. an MCZ Musa , an indoor pellet hopper e.g. Pelleburn or a purpose built hopper. This means that the storage needed varies in size depending on the location and budget. For those tight on space a 1.5m by 1m space is generally more than enough.

For logs the space is larger for the smallest boilers. The boiler is larger, needs more space for a larger flue, and accumulation tank. This is typically 2.5m2

Cost of Fuel

Often the most immediately available fuel is more expensive on the internet. Pellets do range in price, but are frequently £200 per tonne or 4.5p per kWh. (Oil prices were 65p per liter (6.5p per kwh in March and are currently 53p per liter, 5.3p per kWh)

Logs vary more in price and this also varies considerably regionally. For those with a ready supply there is the cost of cutting logs ie your time, or alternatively you can get fuel delivered often at £90-100 per tonne 

This makes the cost of logs about half the price of pellets.

Efficiency and Sustainability

A WBS log boiler can be 90% efficient and a pelleburn pellet boiler can be 94% efficient. Some of the efficiency difference can be put down to pellets being dryer and only pulp, ie no bark.

If your logs are from your immediate surroundings then there is no transport or significant processing costs. In addition some pellets have been artificially dried. Whilst not significant, pellets are transported and there is a manufacturing cost that involves drying wood pulp.

If your logs are the result of forestry or woodland management and the wood is offcuts ie cannot be used for other things, then it is sustainable. This is also true for pellets e.g. if as part of making paper there is sawdust and pulp left over then this waste product can make pellets.

There is a strong argument for logs in terms of sustainability and transport. Unfortunately this does not work for many people due to the availability of local woodland management for our homes and logs are not economic to transport.

Renewable Heat Incentive

Currently the non domestic Renewable Heat Incentive pays the same incentive for log boilers as pellet boilers.

A 30kW log boiler May get RHI payments of  30 (Size of boiler) X 8.3 (higher tariff) X 1314 hours = £3271 per annum.

For an installation of logs or pellets costing between £7-10,000 this would payback in under 3 years before you take into consideration the lower cost of fuel.

A Possible Compromise

If you are finding it difficult to decide whether you want logs or pellets. For many the logs do appeal but there is the extra work involved and will you be happy doing this?

The WBS range of log boilers all come ready to fit a pellet burner ie you can convert your boiler over at a later stage. The pp and pelle ranges of burner are easy to fit and with some minor adjustments to your settings you can be burning pellets.

For more information do get in touch with us using the form on the right hand side or by phoning 01225 580 401


Wood Pellet Boilers – Up to 250 kW

Wood Pellet boilers from NES are robust and up to 40 kW. They also produce a range  of wood burning boilers WBS Active that have a burner flange that allows for a pellet burner unit to be attached.

The WBS Magna is a 250 kW boiler that can burn logs or pellets. You do need to purchase the pellet burner and feed separately. This gives you the flexibility of operation.

This could be ideal for schools, hotels, or larger office spaces in a rural environment.


Wood Pellet Boiler Installations – Some General Rules

As part of our service we assess requirements and properties to help you choose the right system or boiler for your heating and lifestyle choices. This post is all about Wood Pellet Boiler Installations.

For this we asked Tom Jacques, an architect and RIBA Client Adviser based in the South West for some comments.

Tom responded with 3 articles the third of which is below.

Part 3 General rules about wood pellet heating

Rule 1 – Most estimates on websites are unreliable

As the complexity of the system selected increases, the parts and the labour go up in price significantly. However the maintenance levels go down and the efficiency of the system goes up.

Expensive parts do include the pellet boiler which ranges in price from £3000 to £17,000 but also:

The flue – this can cost between £750 and £2000

Accumulation or climate control – between £850 and £2000

Pellet Store – You can use the integrated hopper that will last you a few days at peak load. Otherwise there are several options. A steel hopper may cost between £2000-£3000, as may a flexible liner in steel frame.

Pump sets and other plumbing equipment are also needed, especially if you have several heating circuits.

The labour charge varies from a few days to a couple of weeks depending on the design of the heating system proposed. This may be in the range of £1500 to £6000 with plumbing supplies (e.g. copper pipe) being extra.

Rule 2 – Everyone is an expert

We accept that the market is relatively new. Whilst most MCS accredited installers are very good and knowledgeable we have found that people’s knowledge varies. This includes consultants, other technologies, advice centres, builders, architects etc

If you have a budget and know what you want, do invite several companies to quote. Any risks that there may be can be identified and ironed out.

Rule 3 – Do the sums

We often suggest biomass as we think it has great potential as an alternative to oil and Lpg, particularly where heat loads are higher. Occasionally other solutions, including ground source heat pumps, air source heat pumps, solar thermal, and electrical generation and output devices may be preferable, or used in combination, and should also be considered.

All renewable technologies have the benefit of being able to have MCS accreditation. As such when your house is assessed, they should tell you how much heat you can get from their system, how much it will cost to install and run. It is then a fairly simple process of firstly doing the sums and then secondly having a feel about which technology you like best and works in your situation.

Key considerations for “doing the sums” are to:

  • Understand your own heating needs. What heat did you use last year? For instance if you used 2000 litres of oil you burnt about 20,000 kWhs of energy. At 60p a litre this is £1200. This costs 6p per kWh
  • Get a price for the equipment and installation along with the output or performance, probably in kWs.
  • Understand how the equipment works at its best and its worst so that you can get an idea of operating costs. ie. how many tonnes of pellets do I need to burn? Pellets often release 4800 kWhs per tonne. In the above example this would be approximately 4.2 Tonnes of pellets. This gives a fuel bill of about £800 and a saving of £400. This costs 4p per kWh

For Heat pumps understand the co-efficient of performance (COP). For instance a heat pump will perform differently based on:

The type e.g. Air Source heat pump or Ground source heat pump,

The job it is being asked to do e.g heating water to 60 degrees C

The temperature of the air or ground where the heat exchange is taking place, and maintaining optimum performance.

Each kWh of “free energy” needs electricity to power the heat pump. If the COP is 2:1 then you get 2 units of heat for 1 unit of electricity.

A recent study of heat pumps in 2010 – “Getting-warmer-a-field-trial-of-heat-pumps” by the Energy Savings Trust suggested that the COP or Coefficient of Performance for heat pumps varied between 1.2 and 3.6 with a mid range of 2.2 for ASHP and 2.3-2.5 for GSHP. If electricity is 15p a kWh (then you would be paying between 12.5p and 4.2p per kWh with the majority of outcomes being between 6 and 6.8p per kWh ie a total bill of about £1200. Clearly if you had a PV installation with spare capacity or a “special” rate then you can reduce this cost.

Similarly, if the electricity is obtained through the mains, system losses will be taken into account in any calculation of carbon consumption and overall efficiency.

With the Renewable Heat Incentive, the rates for non domestic RHI have been published and this gives you an idea of the possible rates for domestic RHI in the future. Biomass is 7.9p a kWh, Solar 8.5p, and GSHP 4.5p. For 20,000 kWh’s of heat biomass wood pellets would gain nearly £1600 per annum for 20 years.

Rule 4 – The price of fuel will go up in price

Unfortunately we are in a volatile period for prices. Electricity, gas and oil are likely to keep going up in price. No one really knows by how much. There is greater demand for a diminishing world supply, resulting in a shortfall in the amount of energy to go around. In general oil and gas go up in price when you need it most.

Wood pellets are being made all over the country and there are more pellet suppliers than there are electricity providers (or gas and oil producers). This means it is a more competitive market which is likely to remain price sensitive for some time to come. Clearly there is a potential limit for how many wood pellets can be produced. The main constraint is the supply of raw material either sawdust or recycled wood. Many providers have fixed their prices to give confidence in the industry and it is very unlikely that you will get a monopoly in the same way as other forms of fuel. Still, it is likely to make more sense to order when demand is lowest.

For a good idea of relatively up to date price comparisons do click here

Rule 5 – Simple is best

With all the above points there is a tendency to get confused or wedded to a particular solution which may prove inappropriate, or to get consumed by too much detail at an early stage. Do take advantage of your home as it is. If you are combining alterations with an extension, consider how best use can be made of each element, and what can be best located where. Do ensure that you minimise heat loss as this is usually the most cost effective intervention which can be made. For systems installed do consider carefully how you will use and maintain the buildings and systems installed, for example the trade off between filling a hopper once or twice a week against once or twice a year (and the increase in costs that will result). Do use existing chimneys where possible as this will decrease your costs.

If biomass forms part of your solution, some of the choices you will make will be substantial and make a difference to the costs and effectiveness of the system. Other choices will be a bit like choosing a car. Once you have narrowed down the options by essential criteria, the remaining options will largely do the same job, but preferences can lead to significant price differences even within a model.

Installation costs are normally quite similar between companies for the same job, (it is worth getting alternative quotations to verify this), but the more complex the system, the higher the installation costs.

Tom Jacques

Tom Jacques is an architect and RIBA Client Adviser based in the South West.

Alongside interpreting,defining and meeting clients spatial and aesthetic requirements, Tom prioritises environmental design alongside an understanding of building physics, the use of appropriate technology, and the performance of buildings and their systems in use.

He embraces different approaches in different circumstances, and works where possible with specialists in their fields. Many of his projects involve work with listed buildings and in sensitive settings, and where planning and listed buildings consent is required.

He is not a specialist in any particular product or technology, nor a building services engineer, but is able to offer advice and assistance on projects where required.

If you wish to contact Tom, please contact us and we will pass your comments on to him.


Wood Pellet Heating and The Home Owner

Part 2 – Assessing the issues to be considered by the home owner when choosing wood pellet heating

As part of our service we assess requirements and properties to help you choose the right system or boiler for your heating and lifestyle choices.

For this we asked Tom Jacques, an architect and RIBA Client Adviser based in the South West for some comments.

Tom responded with 3 articles the second of which is below.

1.Do you want your pellet boiler to be a feature or hidden away? Some boilers are designed to be part of the living space. Many of these are Italian. For instance MCZ use ceramic, marble and metallic styling to make their boilers attractive as well as a viewing plate on the flames. It may be more straightforward for these sorts of boiler to take advantage of available chimneys.

2.Do you want a large fuel store that will last at least a month and possibly 1 year? If so you may have to construct a separate fuel store. This will need more space and will increase your costs.

3.Do you want minimum maintenance? You can take advantage of features such as automatic cleaning of the grate and heat exchangers. This will increase costs and probably limit you to a choice of Austrian boilers such as Solarfocus.

4.Do you want Microgeneration Certification Scheme (MCS) accredited boilers and installers? The MCS scheme is about quality. Making sure that boilers are being made and installed properly. The scheme is government supported and gives access to government support.

5.Do you want access to grants or incentives? The government have introduced a Renewable Premium Payment scheme of £950 for biomass. The Renewable Heat Incentive or similar scheme is expected to be introduced for non domestic buildings in November/December 2011. The domestic RHI is expected to be late Summer/Autumn 2012. If you want to be informed about the scheme, use the contact form and receive updates.

6.Do boilers have different running costs? Each boiler has a different efficiency rating. For instance MCZ boilers are 90-93 percent efficient. Solarfocus boilers are up to 96.8 percent efficient. This is more efficient than a wood burner at between 75 and 85 percent efficient. A buffer or accumulator tank to iron out the peaks and troughs of heating and save fuel is often recommended, alternatively weather compensation may fulfil a similar function.

7.How do you choose wood pellets? Local supply should decrease costs of delivery. Do look at the latest lab reports that the pellet supplier has undertaken, alternatively they may have signed up to a quality assurance scheme operated by Hetas or Woodsure. Some pellets are made as a by product of waste and some from virgin wood. Pellets are much better quality than a few years ago. Your boiler may need to be cleaned by your installer, and in the worst cases it can stop working if pellets are of poor quality. Prices of pellets vary by size of load, distance of delivery, and method of delivery. This could be a lorry “blowing” pellets into a fuel store or a pallet of bags. Current prices are cheaper than oil by about 20p a litre and cheaper than gas by about 0.7p a kWh.

Tom Jacques

Tom Jacques is an architect and RIBA Client Adviser based in the South West.

Alongside interpreting,defining and meeting clients spatial and aesthetic requirements, Tom prioritises environmental design alongside an understanding of building physics, the use of appropriate technology, and the performance of buildings and their systems in use.

He embraces different approaches in different circumstances, and works where possible with specialists in their fields. Many of his projects involve work with listed buildings and in sensitive settings, and where planning and listed buildings consent is required.

He is not a specialist in any particular product or technology, nor a building services engineer, but is able to offer advice and assistance on projects where required.

If you wish to contact Tom, please contact us and we will pass your comments on to him.


Wood Pellets and Solar Thermal?

Do wood pellets and solar thermal work well together as a combination?

The simple answer is “yes” with the home owner taking advantage from both the sun and wood pellets or logs.

The disadvantages are that you have to pay for 2 pieces of heating equipment and for 2 installations. However there are plenty of bonuses.

1 The non domestic Renewable Heat Incentive

(for organisations and district heating)

The non domestic RHI will pay out 7.9p per kWh for small scale biomass and 8.5p per kWh for solar thermal.

The rates being slightly favourable for solar mean that each kW you heat using solar is more beneficial for your heating bills and your incentive tariff from hte government will be  a little higher.

2 The domestic Renewable Heat Incentive

Whilst tariffs are not yet decided it is expected to be similar in parity to the non domestic RHI.

3 During the summer

During the summer it is likely that solar can be the only form of heating/producer of hot water. This means no bills.

4 During the winter

During the winter solar takes the edge off your bills according to how sunny it is.

5 No struggling with heating

Solar can struggle to provide heating. Biomass wood pellets have few limitations in terms of “how much” heat you need.

Both solar and wood pellets provide cheaper fuel. The RHI does pay for the installations. With the non domestic RHI starting at the end of November applications can be made directly to Ofgem for these sorts of combinations.

How much is the non domestic RHI worth for wood pellets and solar?

@ 20,000 kWhs per year (small b&b and 15 kW boiler) – £32,000 over 20 years

@ 30,000 kWhs per year (small public house 23 kW boiler) – £48,000 over 20 years

@ 40,000 kWhs per year (Small office block 30 kW boiler) – £64,000 over 20 years

@ 50,000 kWhs per year (small hotel 38 kW boiler) – £80,000 over 20 years

@ 60,000 kWhs per year (3 homes in a district heating system 45 kW boiler) – £96,000 over 20 years

@ 80,000 kWhs per year (A museum) – £102,000 over 20 years

The RHI will pay for the equipment and installation. You also get the considerable benefit of “no more fossil fuel”.

Price watch on fossil fuels November 2011

Gas prices for Wiltshire are 8.850p for Tier 1 and 4.132p thereafter. This equates to about 4.7p per kWh for the average house.

Oil was 60p a litre or 6p per kWh

Both types are more expensive than Wood pellets at £190 per tonne or 4p per kWh.

Locally made solar panels

Green Phoenix make their own solar panels near Royal Wootton Bassett in Wiltshire. High quality and transparent pricing!