Energy from renewable sources

Introduction

Renewable energy comes from continuously available sources that do not rely on exhaustible, polluting fossil fuels like coal, oil and gas. The main sources of renewable energy in the UK are:

• wind - both on and offshore;
• sunlight - solar photovoltaics and thermal;
• water - conventional hydro, and the developing technologies of tidal stream and wave;
• biomass - including wood chip and energy crops.

Bristol City Council were one of the first authorities to purchase green electricity generated from renewable sources, when contracts were negotiated by the Energy Management Unit for the Create Centre and the Records Office (B-Bond) in April 1998.

Properties that are supplied by 100% renewable electricity have been progressively added to meet the target set out in the Energy Policy of purchasing 15% of the council's electricity from renewable sources by 2010. The city council are well on target to meet this, with 14% of green electricity currently being procured.

A significant step in reaching this target was supplying Bristol’s 34,000 street lighting lanterns with green electricity, effective from January 2007.

The list below shows the main sites supplied by green energy:

• CREATE Environment Centre;
• Bristol Records Office & Property Division;
• Amelia Court Council Tax Office;
• Great Western Refuse Transfer Station;
• Wilder House;
• Council House;
• Colston Hall;
• Romney House;
• St Anne's House;
• Brunel House;
• Trenchard Street MSCP;
• City Centre Water Feature.

It is generally considered that green electricity purchase is a good thing as it stimulates the market to provide more and moves the UK forward in meeting its target to have 10% of its electricity from renewable sources by 2010.

Wind farm at Avonmouth

At present demand for renewable "green" energy far outstrips supply capacity. In order to meet our target we will have to generate a certain degree of electricity from renewable sources ourselves.

This is why the EMU commissioned a report on the renewable energy potential of Bristol. We are now looking at the feasibility of getting possible projects up and running and producing clean, green energy.

One scheme is the possibility of siting a pair of wind turbines at a former Shell tank depot on Severn Road, Avonmouth. Should this project come to fruition the two wind turbines would produce a significant contribution to meeting our renewable energy target.

A wind mast was erected to measure wind speeds to see if the site was suitable for wind generation. We are now in the third year of monitoring bird populations and movements, with the intention of discovering if a turbine development would have any impact on the bird populations that use the estuary.

Following this and other surveys, Bristol City Council has commissioned specialists to undertake an Environmental Impact Assessment for the proposed development.

Click on the link for further information about this project: Avonmouth Wind Turbines Project.

Solar energy

In January 2007, the council installed solar photovoltaic (PV) panels on the roof of the Easton Customer Service Point, which has over 25,000 customers a year. Predicted annual energy output is 3,510 kWh electricity a year and equivalent savings of 1.5 tonnes of CO2. It is part of a wider project to install energy efficiency measures and promote energy grants.

The Energy Management Unit hopes to continue investing in solar technology. Feasibility studies were undertaken on 21 non-domestic council-owned buildings. These assessments showed whether solar thermal panels are appropriate for these buildings. The buildings included elderly people's homes, schools and council offices.

Planning approval is being sought for the first two installations using solar heated water at a nursery school and an elderly people's home (EPH). Both of these have a high use of hot water all year round.  If these installations prove to be successful then a roll out programme for further installations is planned.  A Low Carbon Building Programme grant has been obtained for the EPH.

Biomass heating systems

The city council has now installed three biomass boilers and is looking to continue to replace oil and gas boilers at other council owned sites with biomass boilers where feasible.

The installation of biomass boilers has the additional benefits of:

• reducing the energy costs of the council (as wood chip is considerably cheaper than gas);
• benefiting the local economy as money is spent on a local fuel source and not on foreign imports of oil and gas.

The first biomass boiler installation, at Blaise Nursery, won the RegenSW Green Energy Award for 'Best Renewable Energy Project in the South West'. It is also the South West's first wood fuel station, processing wood chip for other biomass boilers installed by the council. As part of the wood fuel station development, a large pole barn was built to store wood chip and a special tipping trailer was purchased for the delivery of wood chip to other council sites.

The Energy Management Unit (EMU) is currently investigating the installation of biomass boilers at The Park, The Museum of Bristol, Ashton Court Mansion House, and Bristol South Pool. Furthermore, four new schools are being built as part of a PFI project for the council. These schools will also be heated by biomass boilers.

The current boilers are utilising wood chip from the council's parks. However, as this is a finite resource, the EMU is investigating both the growing of short-rotation coppice willow on council land and, in conjunction with Bristol Parks, the greater management of the council's own woodland. Both of these actions will have additional beneficial effects for the city's wildlife as the coppicing and management of woodland increases biodiversity.

For more information see the information sheet (pdf, 325 KB) about the Biomass Boiler now installed at Blaise Nursery.