The Azimuth Project
Renewable energy in a small remote village

Contents

Idea

This is a case study of the potential for renewable energy in a small remote village in Scotland, called Durness. It could be described as a place with more wind than people. There have been plans to develop renewable energy in the area for a few years. This page concentrates on what currently (Oct 2011) seems the most likely possibility: a single wind turbine with peak output of 500kW. The idea is that the turbine would be owned by the community.

Technology

Wind turbines

A survey in 2007 on the potential for wind turbines in the area said:

The preferred choices of turbine for development are a single reconditioned Vestas V39 (500 kW capacity) and 2 No Enercon (E33) turbines (individual capacities of 330 kW). These scales of turbine were primarily chosen to best fit the current available capacity on the local grid to export. It is expected that all of the electricity generated by the turbine will be exported on the national grid.

Some basic statistics from the survey:

SpecificationEnercon E33Vestas V39
Rated Capacity330 kW500 kW
StatusNewReconditioned
Ground to blade tip61 m60 m
Estimated operational life20-25 years12-15 years

Hydro

[todo]

Money

Feed-in Tariffs

The UK Feed-in Tariffs are described by Feed-In Tariffs Ltd. They give the tariff levels, and the relevant ones for wind turbines at the scale planned for Durness are:

ScaleTariffDuration
100 - 500kW19.7 p/kWh20 years
500kW - 1.5MW9.9 p/kWh20 years

The tariff is index-linked. The meaning of ‘Scale’ is unclear. According to the FAQ:

The Government has not yet finally decided how it will define ‘capacity’ - the parameter used to define where the tariff levels are set. Logically the so-called ‘declared net capacity’ (DNC) should be used to allow for variations between renewable energy types.

‘Declared net capacity’ is not that much clearer. However it seems that if DNC was used it would allow wind turbines much larger than 500kW peak output to receive the 19.7p/kWh rate.

If a project generates 1MW, do you get 19.7p/kWh for the first .5M, and 9.9p/kWh for the rest? Otherwise, a 1MW project costs more and produces no more income than a .5MW one.

Income

500kW operating at an average 30% capacity means 150kW. At 20p/kWh, that is £30/h, or £260k/year. Durness is windy, so 30% is conservative.

Costs

The main upfront cost is installation. RenewableUK provided some onshore wind installed costs in June 2010:

Recent published installed costs for UK wind farms are in the range £1,250/kW to £1,573/kW, with a weighted mean of £1,334/kW. This suggests that Ofgem’s recent estimate of £1,200/kW is on the low side.

500kW at £1400/kW is £700k, but the figures are for a wind farm, not a single turbine. Perhaps £1M is more like it. RenewableUK also give a figure for operation and maintenance costs of about £50/kW/year. The major costs are then:

  • About £1M installation cost.

  • There would also be a cost to upgrade the electricity grid, which would have to be paid by the local community. This cost is unknown, but might be very large.

  • Operation and maintenance costs of about £25k/year.

  • A loan would be required, so interest would have to be paid on that.

But before any of these become relevant, there are ‘pre-development’ costs.

Pre-development costs

Pre-development costs are estimated at £130k, for feasibility studies, planning applications, etc.

Loans may be available. They are expensive (10% interest) but can be written off if the project fails, given some unclear conditions. Here are links to one, two, three, four case studies for similar projects. If the project failed and the loan was not written off, somebody would have to pay it back. This makes people nervous.

Pre-pre-development costs

£5k to pay the electricity company (SSE Power Distribution) to do a survey to find out how much they would charge to upgrade the grid. According to a free ‘desktop survey’ this might be up to £2M.

The community

Durness

The population of Durness is about 350 (according to this report by CVS North). Typical domestic energy usage in Scotland is around 2000 kWh/year per person (according to figures from The Energy Systems Research Unit) so 350 people use around .7M kWh/year. A 500kW turbine at 30% capacity would generate nearly twice Durness’s domestic electricity usage.

If the project failed at the pre-development stage and the loan was not written off, that would be about £400 owed per person in Durness.

Graham Jones lives in Durness.

Durness Development Group

The Durness Development Group

category: action, energy