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Community Development of Small Scale Hydropower. Castle Douglas Town Hall 19 th February 2013 James Buchan CES Development Officer – Central Scotland & Fife. Why Hydro?.
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Community Development of Small Scale Hydropower Castle Douglas Town Hall 19th February 2013 James Buchan CES Development Officer – Central Scotland & Fife
Why Hydro? Small-scale hydropower one of the most cost-effective and reliable renewable energy technologies to be considered for providing clean electricity generation. High efficiency (70 - 90%) High capacity factor (typically >50%), compared with 10% for solar and 30% for wind High level of predictability Slow rate of change Good correlation with demand Long-lasting and robust Source of revenue (FIT’s)
Most common uses Community hydro schemes - 3 broad categories; Off-grid - power for remote communities not connected to grid e.g. hydro on Eigg and Knoydart Off-grid or grid-connected schemes providing electricity and/or heat to a community building e.g. Abernethy Trust Income-generating projects to feed into the grid to provide long term community revenue e.g. Callander Community Development Trust
How does it work? Converts energy in falling water into electrical energy. Most small schemes ‘run of river’- divert flow using intake weir. Weir incorporates screen to filter debris (may include fish pass). Weir diverts water into ‘penstock’ (pipe which carries water downhill). Water directed by pipeline into turbine -strikes a wheel, which turns a generator and produces electricity. Water returns to river through a ‘tailrace’ Electricity is sent through cables to the national grid or to the building it powers.
Site Area and Suitability Key requirements : Head – drop in height over length of river / burn e.g. waterfall, old weir, gradual incline over distance Flow – the greater the volume of water flowing downstream, the greater the potential energy of system. Both low head/high flow and high head/low flow schemes common - combination of both will generate greatest amount of energy.
The Flow Rate (Q) is the volume of water passing per second (m³/sec). TheGross Head (H)is the maximum available vertical fall in the water, from the upstream level to the downstream level (m). The Net Head– after losses incurred when transferring the water into and away from the machine.
Power & Energy Energy = amount of work done / ability to do work (Joules/ kWh) Power = energy converted per second, i.e. rate of work being done (W / kW /MW) Best turbines have efficiencies in range 80 - 90%. Micro-hydro systems (<100kW) tend to be 50 to 80% If we take 70% as a typical water-to-wire efficiency for system, then power of system shown by: P (kW) = 7 Q (m³/s) H (m)
Other Site Requirements Good access / routes for new track for construction of weir or dam, penstock , powerhouse. Powerhouse located close to power lines / building it will be providing energy to - cuts down on energy losses / cost of laying cables long distances. The river / burn should have good flow all year round to maximise power output / payback of the scheme Most designed on the mean flow of river. Sizing to peak flows not advised - turbine will not work as efficiently when the flows are lower for much of year.
Turbines Selection of turbine depends upon site characteristics - head / flow, running speed of generator and whether the turbine will be expected to operate in reduced flow conditions. Reaction Turbines Encased in water Frances (spiral) Propeller Kaplan Impulse Turbines Jets of water Pelton Turgo Crossflow
Developing a Community Hydro Project Large number of communities progressing and successfully completing complex renewable generating projects Reduce community dependence on fossil fuels Greater awareness of energy issues Increased energy efficiency across the community Reduction in energy costs and carbon emissions Income generated can be significant Self sufficiency for community organisations and re-investment in the local area
Community consultation Essential when considering large community developed / owned renewable generation projects. Local support essential to gain commitment of volunteer effort / resources to progress such a project. Crucial in convincing funders that community really wants project. If project is to benefit community, they need to have a say in how it progresses. Community will also therefore ‘own’ the project in more than just the legal sense.
There are three main initial areas which should be discussed: Is there a real need across your community for an energy generation project and / or a long –term source of revenue? Does your group have the commitment and capacity to take forward a large and complex project? What viable renewable energy resources do you have available within your locality?
Site selection & Land Ownership Key is land ownership / gaining access If community owns land should not be problem If not, permission / access to be gained from landlord Agree with landlord exclusive rights to develop /gain lease if planning consent gained Needs to be for lifetime of project - 25-50 years Important to secure access /use of site before planning granted and to include area for access /pipelines construction Negotiate rental rates - professional opinion and market rates should be obtained. If site leased rent could be fixed fee or vary according to power output
Pre-feasibility Study Any developer should seek independent professional advice before committing significant finance to the design and construction of a small-scale hydro scheme. http://www.british-hydro.org/ http://www.scottishrenewables.com/ An experienced hydro professional should be able to indicate whether a site is worth considering . Will typically require no more than 2-3 days’ work and will cost between £300 and £1000. A minor investment at this stage could save much greater expense and potential complications later in the development process.
Main issues that should be considered in a preliminary investigation are: Existence of a suitable waterfall or weir and a turbine site Consistent flow of water at a usable head Acceptability of diverting water to a turbine Site access for construction equipment Prospect of a grid connection at reasonable cost Social and environmental impact on the local area land ownership /securing / leasing land at reasonable cost Initial indication of design power and annual energy output Accuracy of information may only be +/- 25% Should be sufficient for deciding whether to proceed to a more detailed feasibility study.
Full feasibility study Uses accurate data and looks closely at costs Can take project from initial idea to final design Will support applications for project finance / licenses. Cost of full feasibility study carried out by an independent consultant depends on its scope and on the specific characteristics of the site, but would typically be £7,500-£10,000.(grants from CES)
Hydrological Survey. Would produce a flow duration curve. Modelling and using catchment rainfall information Low Flows 2 software (used by SEPA and banks) Based on long-term rainfall / flow data, together with knowledge of the catchment geology and soil types. This long-term information might be backed up by short-term flow measurements. The study should also include an estimate of the required compensation flow.
System design. • Would include a description of the overall project layout, including a drawing showing general arrangement of the site. • The prominent aspects of the works should be described in detail, covering: - Civil works (intake and weir, intake channel, penstock, turbine house, tailrace channel, site access, construction details) - The generating equipment (turbine, gearbox, generator, control system) - Grid connection
System costing. A clear system costing would include a detailed estimate of the capital costs of the project, subdivided into: - Civil costs - The cost of grid-connection - The cost of electro-mechanical equipment - Engineering and project management fees Estimate of energy output and annual revenue. Would summarise the source data (river flows, hydraulic losses, operating head, turbine efficiencies and methods of calculation) and calculate the output of the scheme in terms of the maximum potential output power (in kW) and the average annual energy yield (kWh/year) converted into annual revenue (£/year).
Grid Connection What might influence grid connection costs? Remote areas – can be expensive for larger schemes Grid designed to distribute power from large centralised generators to eventual small rural household loads. DNO sometimes unenthusiastic – voltage rise and liability Monopoly within defined areas means that connection costs may be unaccountably high Beware additional costs: - HV connection earthing – (HV and LV earth systems) - Wayleave agreements with landowner
Budget Study (~£500): Apply to DNO – tell them where, why and size of generator If there is capacity they will give approximate connection costs Pro’s – cheap / only takes a month, Con’s – no place in queue Network Study (~ £1500 - £3000): Can be DNO or 3rd party Can ask to explore different scenarios – e.g. We want 800kW but can we connect a 400kW any earlier Takes 3 months – will look into capacity at that time with more accurate costs Pro’s – more info / looks at a few options Con’s – no place in queue / only capacity at that time
Formal grid connection application (Free): No charge, but 3 months to get back Will give costs for cheapest option No different scenarios, will only look at what you ask Will register you on the system Will ask if you want to put down a deposit (%age of total costs) Pro’s – Free, puts you in queue / books capacity Con’s - If don't take offer within time limit lose place in queue Time limit – SSE: 1 month / SP: 3 months
Grid Connection deposit: Based on a specific generator / Turbine If installed capacity goes up the have to re-apply If location changes then void If date of connection changes significantly then void Cost of feasibility study if done comes off cost of deposit Good to keep DNO updated as offer will lapse Deposit refundable (less any work done) if showstopper e.g. no planning permission etc
Low voltage connection (<200kW/300kW): typically £10,000 - £30,000, depending on proximity of 11kV or 33kV network No switchgear required <200kW, includes earthing and pole mounted transformer High Voltage Connection (>300kW): typically £40,000 - £100,000 or more. Additional costs of substation building (up to £25,000) to accommodate HV switchgear (above 200/300kW then need switching to turn it off), plus costs for the transformer / earthing Earthing design and ground resistivity studies (up to £5,000) depending on site and conditions Contestable and non-contestable works (3rd party usually for contestables as DNO expensive) DNO does not usually guarantee timescales
Finalise Legal Structure for Project Essential to have proper, legally recognised group structure in place Helps to ensure those undertaking the project are clearly accountable to community. Most projects taken forward by subsidiary of main community organisation. Company limited by shares, all shares held by the parent community body Established non-profit distributing model - helps ensure community body has full control over the subsidiary - volunteers involved not personally liable.
Project Design Resource / feasibility assessments will drive project design. Planning permission - need to submit full detail / design of project. Communities advised to develop business model during project design to ensure costs and project makes financial sense. http://www.businesslink.gov.uk http://www.scottish-enterprise.com For detailed design community will need technical assistance to ensure site incorporated into area with minimal impact. The feasibility study provides initial information required for design but additional work needed to ensure all impacts addressed.
Planning Permission Planning permission needed for all large renewable developments Hydro projects up to 1 MW in size dealt with by local authority Environmental Impact Assessment (EIA) Site in 'sensitive area' />0.5 MW/dam -need for EIA must be considered Impacts on hydrology - ecology should also be considered Planning authority - definitive guidance to submit a robust application.
Environmental Assessment (EA) Impact assessments - soil, hydrology, wildlife, visual ‘ noise impact, social, economic factors Breeding season delays to planning Assessment of impact on fish life SEPA guidance on compensation flow Designated areas – SSSI, SAC, SPA, NNR, AONB
Some Important Flora and fauna Migratory fish Bryophytes (Mosses and liverworts) Freshwater mussels Otters, water voles, bats and badgers Large native trees Invertebrates – e.g. Crayfish Dippers, kingfishers, other birds etc Amphibians and reptiles – frogs, toads, newts and snakes
SEPA Hydro schemes require water use licence from SEPA Contact well in advance of application. All developments require CAR authorisation for abstractions / weirs and dams / engineering http://sepa.org.uk/water/hydropower.aspx Submit application same time as planning
Information Required: Head & Flow Turbine efficiency Installed capacity Abstraction point / source type Grid reference / maps Intake structure Construction method statement Rate of abstraction Discharge point / % returned Operating regime Rights to water
Project costing and financial planning Project costs will arise from: Project development, planning consent ,consultancy work, planning report Advice /setting up trading company Grid connection costs Financing costs – loan repayments, overdraft interest, accountancy advice Insurance costs - construction / operation Turbine and civil infrastructure costs
Operational Costs: Business rates Land rental Administration / salaries Non warranty service and maintenance Warranty Turbine monitoring – BT lines etc Contingency Example financial spreadsheet
Financing a revenue generating project For community groups financing of project is a large undertaking. Projects can cost over £1million and have significant operational costs Stages of financing a large project; Pre development Planning preparation Post planning through to construction Community projects will require a mix of finance to become viable (debt (bank), grant and equity)
The initial stages of development / planning are the riskiest - will require secure funding Final phase, once planning consent and a grid connection have been confirmed, should attract commercial finance All funders will perform some due diligence on the project
Scottish Government's Community and Renewable Energy Scheme (CARES) CARES Urban Support Programme CARES Pre Planning Loan Fund (Rural Business and Communities) CARES Post Planning Loan Fund (Open to Communities) CARES Infrastructure & Innovation Fund CARES Start Up Grant
Construction of Project Contracts for hydropower installations tend to be on a turnkey basis Management of entire construction phase, turbine supply, infrastructure transport Match between project design and installation is crucial
Operation & Maintenance Maintenance and servicing of technologies and infrastructure required for the lifetime of project. Essential there is provision for these included in the supply of a turbine, and that this is accounted for in business and financial planning. May be provided under warranty for first few years of the project Can sometimes be extended throughout the lifetime of the project. Also possible to outsource O&M services from other companies
Many thanks for listening James Buchan CES is Scotland’s community energy charity. We are a membership organisation made up of community groups, with voluntary directors elected by our members. We have a membership scheme in which eligible groups can become members of CES for free. Details can be found on our website and leaflets are available in the foyer.