The dripping of a tap in your house can be more of an annoyance than a leaking water main in the street, even though the amount of water wasted from the tap is small compared to that of the water main. The importance of an issue to you depends on how you perceive it to impact your life. Small issues can seem more important than more serious ones purely by presenting themselves to us in our own houses, day in, day out.
This problem was illustrated recently in BBC 2's Wind Farm Wars. The program featured the dispute between residents living in Devon to a proposed nearby wind farm at Den Brook. Since its inception in 2004 the project has been subjected to constant objections and appeals by locals.
The Local Perspective
The resident's argument is centered around the potential noise caused by the turbines and the impact on the look of the valley. The wind farm is expected to generate power for between 10,000 and 13,000 homes or 49% to 65% of Devon's power needs. The amount of time and money wasted during the 7 year delay is vast, during this time the power for these houses has almost entirely come from coal, gas and nuclear sources.
The National Perspective
Estimations of the amount of power that comes from renewable sources in the UK vary between 5.9% and 6.5% which is well below our target of 10% by 2010. Admittedly on-shore wind farms aren't as effective as off-shore sites, one way of measuring the efficiency of power generation is their "load factor", which is their actual output divided by their potential output. On-shore scores 21%, compared to off-shore at 29%, conventional power station are around 50%. Overall the cost per unit of electricity from wind farms is 3 - 4p per unit, which is comparable to the cost per unit for a modern coal power station at 2.5 - 4.5p, and is cheaper than nuclear at 4 - 7p. Renewable sources such as on-shore wind farms might not be the most efficient source of power, but they're definitely better than burning fossil fuels.
The Global Perspective
Carbon Dioxide emissions are a global issue, as a country we contribute 1.8% towards the total output. Out in front by a huge margin are China at 22.3% and the United States at 19.9%. These countries have huge populations so in order to get a more balanced picture we can look at the total carbon dioxide output per person. These are the top 20 CO2 producing countries ranked by tonnes per person. The Global Total is included as way of a benchmark.
In the UK 65% of our carbon emissions come from burning fossil fuels to create electricity. Using this we can work out how much CO2 is emitted per person due to burning fossil fuels to create electricity:
572,617,000 x 0.65 = 372,201,050 tonnes of CO2 per year as a country.
372,201,050 / 62,008,048 = 6 metric tonnes or 6,002 kg of CO2 per person per year.
The Den Brook wind farm could produce electricity for a minimum of 10,000 people, that means that the electricity wouldn't have to be generated by burning fossil fuels, which is a saving of 60 million kg of CO2.
Due to the 7 year delay this means that at least 420 million kg of CO2 has emitted unnecessarily.
1 gallon of petrol burnt in a car causes 10.4 kg of CO2 to be emitted. Each year that goes by without Den Brook being built is equivalent to 5.8 million gallons of petrol being burnt, the 7 year delay is equivalent to burning 40.4 million gallons of petrol.
This government report from 2008 states that petrol cars in East, Mid, North and West Devon used 108,300 tonnes of petrol per year which is equivalent to 28.7 million gallons of petrol. The proposed wind turbines would be like taking 20% of the cars off Devon's roads.
The residents of Den Brook are entitled to their views, however its clear to see what has a greater impact on the environment. I know I'd rather look out of my window and see a few turbines than 6 million gallons of petrol on fire.
What happens if the wind doesn't blow?
One of the major opposing views against wind farms is that we don't get consistent enough wind in the UK to make them viable and that the billions spent on them could be better spend. Wind speeds have been lower in recent years, however this doesn't necessarily mean this is part of a general trend. The Department of Energy and Climate Change publish statistics on wind speeds in the UK.
A study in 2007 by Garrad Hussan concluded:
In terms of cost per unit wind farms are one of the cheaper options for renewable power but alternatives still have to be used for times when the wind simply doesn't blow, new advances in solar and biomass electricity production may hold the answer.
Desertec are a company who are planning on building an array of solar thermal power stations around the world. The technology is still fairly new, as are the HVDC power lines required to transmit electricity over long distances, this means that the cost per unit is still relatively high, however the cost and efficiency will undoubtedly improve in the future. Many solar thermal power plants are already in use in Spain and other locations around the world with large numbers under construction. It is estimated that if only 1% of the Sahara Desert was used for solar thermal power stations it would generate enough power for the entire planet.
572,617,000 x 0.65 = 372,201,050 tonnes of CO2 per year as a country.
372,201,050 / 62,008,048 = 6 metric tonnes or 6,002 kg of CO2 per person per year.
The Den Brook wind farm could produce electricity for a minimum of 10,000 people, that means that the electricity wouldn't have to be generated by burning fossil fuels, which is a saving of 60 million kg of CO2.
Due to the 7 year delay this means that at least 420 million kg of CO2 has emitted unnecessarily.
1 gallon of petrol burnt in a car causes 10.4 kg of CO2 to be emitted. Each year that goes by without Den Brook being built is equivalent to 5.8 million gallons of petrol being burnt, the 7 year delay is equivalent to burning 40.4 million gallons of petrol.
This government report from 2008 states that petrol cars in East, Mid, North and West Devon used 108,300 tonnes of petrol per year which is equivalent to 28.7 million gallons of petrol. The proposed wind turbines would be like taking 20% of the cars off Devon's roads.
The residents of Den Brook are entitled to their views, however its clear to see what has a greater impact on the environment. I know I'd rather look out of my window and see a few turbines than 6 million gallons of petrol on fire.
What happens if the wind doesn't blow?
One of the major opposing views against wind farms is that we don't get consistent enough wind in the UK to make them viable and that the billions spent on them could be better spend. Wind speeds have been lower in recent years, however this doesn't necessarily mean this is part of a general trend. The Department of Energy and Climate Change publish statistics on wind speeds in the UK.
A study in 2007 by Garrad Hussan concluded:
One of the biggest criticisms of wind farms is that they are very costly to the tax payer, last year the subsidies paid by the UK government came to £1.1 billion, which works out to £18 per person."The indices appear to show no discernable pattern from one year to the next and therefore it is reasonable to assume annual mean wind speeds are randomly distributed." Long Term Wind Trends in Northwestern Europe - 2007 Garrad Hussan
In terms of cost per unit wind farms are one of the cheaper options for renewable power but alternatives still have to be used for times when the wind simply doesn't blow, new advances in solar and biomass electricity production may hold the answer.
Desertec are a company who are planning on building an array of solar thermal power stations around the world. The technology is still fairly new, as are the HVDC power lines required to transmit electricity over long distances, this means that the cost per unit is still relatively high, however the cost and efficiency will undoubtedly improve in the future. Many solar thermal power plants are already in use in Spain and other locations around the world with large numbers under construction. It is estimated that if only 1% of the Sahara Desert was used for solar thermal power stations it would generate enough power for the entire planet.
