We are completely reliant on energy as farmers, from powering machinery and lighting sheds, even just moving around the farm, energy is indispensable. However international oil prices have quadrupled in the last ten years, and coal and gas prices more than doubled, and further increases are expected. There are also long term energy supply challenges as fossil fuels are used up (see the Energy and Food Securitysection), therefore as farmers and growers we need to take action to cushion the impact of these twin factors.
Energy on your farm
Energy generation is important, but don't forget to take the following approach first:
- Reduce your usage
- Increase your energy efficiency
- Install renewable energy options
Monitoring results wherever possible using meters and ensuring consumption doesn't go up in one area just because reductions have been made in another area are both important. See the Energy Resilience section for more on reducing energy use and improving energy efficiency.
Generating renewable energy is a good way to insulate our farms against rising costs. Recent increases in gas prices for example have been due to wholesale price rises on the international market, while 'home-grown' renewable energy, such as solar, wind and biomass, face no such pressures. Renewables also help ensure a secure supply of energy.
Unlike fossil fuels (oil, gas and coal), renewable energies do not 'run out' (see theEnergy and Food Security section of the toolkit for more on declining fossil fuel supplies) – they harness the natural cycles of the Earth (such as sunshine and wind) and are therefore an 'unlimited' resource in terms of the human timescale. It is another way to harness the productive power of the land, which we as farmers and growers appreciate more than most.
On-farm renewable energy options
Renewable energy can provide power (electricity) for lighting, machinery and appliances and direct heating or cooling for sheds, farm buildings, grain storage and offices. All installations should be carried out by MCS accredited companies (Government approved installers) and the installer's financial and energy generation projections examined carefully before committing to a project.
We cover farm-use scale projects below, but we as farmers are in a unique position compared to other industries, in our ability to consider large scale projects on our land. Such projects (typically over 2MW in capacity) are technically, financially and legally distinct from smaller scale projects and require detailed, tailored advice.
Renewable energy technologies suitable for an on-farm setting;
Solar panels – Produce either electricity (from photovoltaic, or PV, panels) or heating for hot water (solar hot water panels). Solar panels convert the Sun's energy into electricity or heat and work even on cloudy days. Attractive returns are still available from the Government's Feed-in-Tariffs (FiTs) scheme. Panels are most frequently mounted on roof space so they don't interfere with day to day business activities and require minimal maintenance, therefore are very convenient.
Cuts to the solar PV FiT rate will be introduced from 1 July 2012 and installations on domestic and non-domestic roofs require minimum levels of energy efficiency – buildings rated below band 'D' on an Energy Performance Certificate will receive a lower payment (currently 9p/kWh compared to 21p/kWh). See the Energy resiliencesection for details on improving your energy efficiency. Many companies also offer a no upfront-cost option renting roof space for panels from farmers but retaining the income.
Financial incentives – Solar PV - The top rate is 21p/kWh (the unit for electricity generation and use), for systems under 4kW in size, to 8.9 p/kWh for large installations from 250 kW to 5 MW. A full list of the solar PV tariffs is available here. All FiTs installations can also claim 3.2p per unit supplied to the national grid (ie not used on site).
Solar hot water - Support is provided for non-domestic installations under the Renewable Heat Incentive (RHI), with payments of 8.9p per unit of heat (kWhth). Domestic payments are planned to be introduced from summer 2013 following a consultation.
Consider if – Solar panels are suitable for many locations, results will be best if you have South facing roof space that is not over-shadowed. Make sure roofs can support the weight (have a survey), or you have space for a ground mounted system.
Background information on solar power from the Solar Trade Association
Wind turbines – Provide electricity for on-farm use and for export to the grid. Available in a range of sizes, from large scale (1.5 MW, 120m high), to small scale (5 kW, up to 10m high). Turbines require careful siting and several factors to be taken into consideration, including; wind speed (above at least 5m/s), proximity to the nearest properties, grid access, nearby radar and airport installations, and visual impact. Your local planning department should be consulted early on in the process. When positioned correctly and with the right conditions, wind turbines can generate very attractive financial returns for your business.
Financial incentives – Current rates range from 28p/kWh for installations 1.5 -15 kW in size, to 4.9p/kWh for those over 1.5 MW.
Consider if – You have good wind speeds (check the database below) and have a site at least 300m from the nearest home, with no airports or radar sites nearby.
Check your wind speed using the National Windspeed Database here
Ground source heat pumps – Generate heat for space and water by using underground pipes to absorb the natural heat of the ground, which stays at a near constant temperature even during winter. Horizontal or vertical trenches must be dug to bury the pipework – some outdoor space near the installation is therefore essential. The Renewable Heat Incentive (RHI) provides payments for heat produced from ground source heat pumps in non-domestic settings even if it is all used on site. The scheme operates for non-domestic buildings at present and will open for domestic buildings in summer 2013.
Ground Source Heat Pump cables before burial (Mark Johnson)
Financial incentives – The non-domestic RHI payment rates are 4.7p/kWhth (for installations under 100 kWth in capacity) and 3.6p/kWhth (installations over 100 kWth). In a domestic setting, the pumps are eligible for a grant of up to £1250 until 31 March 2013 - conditions such as minimum insulation levels apply (more here).
Consider if – You have suitable outdoor space for buried pipework
Information on costs, maintenance and more general information is available from the Energy Saving Trust here
Water source heat pumps - Require a body water near to the heat baseload demand - coiled pipework is sunk to the bed of the water body rather than buried underground and the natural heat of the water provides the energy in the same way as with a ground-source heat pump.
Financial incentives – Eligible for a grant up to £1250 until 31 March 2013, when installed in a domestic setting - conditions such as minimum insulation levels apply (more here). For non-domestic installations, the RHI payment rates are the same as for ground source pumps- 4.7p/kWhth (for installations under 100 kWth in capacity) and 3.6p/kWhth (installations over 100 kWth).
Consider if – You have high heating demands and a suitable stream, reservoir or pond which is not regularly drained and located within 50m of the heating baseload. You can accept and work within the uncertainties surrounding future financial incentives.
Air source heat pumps – These are often directly attached to the outside of buildings and therefore do not require the space necessary for ground source heat pumps so are suited to many locations, particularly where space is an issue. They provide heat for a range of uses including direct heat and hot water. They emit a noise roughly equivalent to a dishwasher when running and planning rules are that they should not be sited too near to neighbours.
They work by taking heat from the outside air and can operate in winter temperatures as low as -15°C.
Financial incentives – Not currently offered, but payments may also be available under the Renewable Heat Incentive following a consultation in autumn 2012.
Consider if – You have high heating demands but don't have the space for a ground source heat pump. You can accept and work within the uncertainties surrounding future financial incentives.
Read the Energy Saving Trust's guide to air source heat pumps here
How ground and air source heat pumps work (Source: idea.gov.uk)
Biomass boilers – Generate direct heating for buildings by burning wood (logs, waste and trimmings, or pellets - termed biomass) that could come straight from your farm. They can also be used to heat hot water systems. Especially if replacing electric heaters, biomass boilers offer considerable savings and generate income from the Renewable Heat Incentive. Sufficient storage space near the boiler is required for the biomass itself. Biomass boilers can operate either entirely automatically; requiring only regular refills and maintenance but the largest amount of storage space, semi-automatically; requiring regular manual supply of the boiler, via a gravity fed pellet system which is best for sites with less storage space, or using a Combined Heat and Power plant (see below) using waste wood or offcuts.
Financial incentives – Financial support under the RHI is currently available at the following rates: 8.3p/kWhth for first 1,314 hours use, 2.1p/kWhth after this for installations under 200kWth. For systems 200-1000 kWth in size the rates are 5.1 and 2.1 p/kWhth, and there is a flat rate of 1p/kWhth for any system over 1000 kWth. You may be eligible for a grant if considering 'energy crops' such as miscanthus to power biomass boilers – find out more here. There are several ethical and practical considerations regarding energy crops which should be taken into account.
Consider if – You have high heating demands and your current source of heat is electricity or oil
More information on biomass boilers
Hydroelectricity – Hydroelectric systems ('micro-hydro' or 'hydro power') use water flowing through a turbine to run a generator and create electricity. Steeper watercourses and faster flowing channels create more energy. They can be installed in different sized watercourses or 'retrofitted' onto some existing weirs. The Environment Agency need to be consulted when considering developing a hydro project, and energy generated is eligible for Feed in Tariff payments just like energy from solar panels and wind turbines.
Financial incentives – Current rates are: up to 15 kW; 21.9p/kWh, 15-100 kW; 19.6p/kWh, 100-2MW; 12.1p/kWh and over 2MW; 4.9p/kWh
Consider if – You have a fast running stream or river on your land suitable for a small diversionary channel
More information on hydroelectricity from NFU Energy Farming
Combined Heat and Power (CHP) – CHP units can provide both electricity and heat by utilising fuel usually only used to create either heat or electricity, to create both. They can be fitted in domestic (micro-CHP) or large non-domestic (packaged or mini-CHP) buildings. Packaged and mini systems can be designed to continue providing power to important machinery in the event of a power cut but most require mains gas supplies to operate, although biomass can also be used as a fuel. Large plants can also be designed to provide cooling ('trigeneration'). The viability of non-domestic mini-CHP depends on the level of consistent demand for the heat and electricity produced, so buildings which only require heating for part of the year or a few hours a day are not suitable. Manufacturing or drying processes would be well suited to a CHP plant as baseload demand is high.
How a CHP plant works (Source: idea.gov.uk)
Financial incentives – CHP qualifies for FiTs, with domestic scale micro-CHP attracting payments of 11p/kWh (and the export tariff of 3.2p/kWh). Non-domestic RHI payments are for biomass fuelled systems and range from 8.3p/kWhth for the first 1,314 operating hours for smaller plants up to 200 kW, to 5.1p/kWth for larger plants between 200 and 1000 kWth.
Consider if – You have a high and consistent demand for heat and power. You want to ensure energy supplies for critical infrastructure in the event of grid power cuts.
Overview of Combined Heat and Power plants from CLASP
Anaerobic digesters – Generate electricity, heat, and a natural fertiliser by-product ('digestate') that can replace chemical fertilisers. Anaerobic digestion (AD) plants work by breaking down matter added to them without using oxygen. Feedstock can include manure, arable crops such as maize, food waste, and other sources such as sewage. AD plants generate income and save money in three ways – Feed in Tariffs from the electricity produced, Renewable Heat Incentive from the heat produced, and financial savings from the reduction in chemical fertiliser use. If handling waste sources, 'gate receipts' for disposing of this waste may also be generated. Planning must involve the Environment Agency and indicate a clear plan for how the digestate generated will be used. There are currently fewer than 100 AD plants in the UK, while Germany has over 4000; therefore there is significant scope for expansion and manufacturers are targeting farmers, with joint ventures, land rental and asset financing deals. Contact ADBA for more information, who currently offer a free consultancy service for farmers.
Anaerobic Digestion Plant (Source: Alex Marshall)
Financial incentives – The payment rates for AD from FiTs are; 14.7p/kWhth for plant capacity up to 250kW; 13.6p/kWhth where it is 250-500kW; and 9.9 p/kWhth for installations over 500kW. The RHI payment for AD plant heat is 7.1 p/kWhth.
Consider if – You have suitable and sufficient feedstock(s) (or can source these). Fertilisers are a major cost for your farm and you can use the digestate produced (or find someone else who can)
More information about on-farm anaerobic digestion from the NFU
More information on renewable energy:
Background information on renewable energy technologies:http://www.greenfacts.org/en/energy-technologies/links/index.htm
Carbon Trust Renewable Energy guide for business:http://www.carbontrust.com/media/7379/ctv010_-_renewable_energy_sources.pdf
Energy Saving Trust guide to renewable energy technologies:http://www.energysavingtrust.org.uk/Generate-your-own-energy
Find an accredited renewable energy installer near you from the MCS scheme:http://www.microgenerationcertification.org/mcs-consumer/installer-search.php
Full list of Feed-in-Tariff payment rates as of April 2012:http://www.ofgem.gov.uk/SUSTAINABILITY/ENVIRONMENT/FITS/Documents1/Feed-in%20Tariff%20Table%201%20April%202012.pdf
Full list of non-domestic Renewable Heat Incentive tariff payment rates as of April 2012:http://www.ofgem.gov.uk/e-serve/RHI/Documents1/Tariff%20adjustment%20for%20the%20year%20from%201%20April%202012.pdf