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So it seems the French energy company won't after all be taking on the building and running of British Nuclear power stations. I'm tempted to say "nice try Gordon." Government plans were to get a new generation of reactors built by the private sector. The reason they want the private sector involved is because the government doesn't want to be carrying the risk. I'm not talking about the risk of a catastrophic accident or a terrorist attack but the financial risk. According to the National Audit Office the cost of decommissioning Britains existing nuclear power plants has risen by £12 billion to £73 billion since 2005. In truth no-one knows just what these costs will eventually amount to. But the Government, keen not to face similar open ended financial commitments in the future, has made it clear that bids to build and operate must include detailed and costed proposals for decommissioning these new reactors. EDF is actually owned by the French Government. In effect future decommissioning costs of British reactors would have been shifted from UK tax payers to French taxpayers. So you have to say "nice try Gordon."
So why is the Government so keen to persue the nuclear option. In part I'm sure because there doesn't appear to be another option. Nuclear currently supplies approximately 20% of our electricity, with gas generating about 40% and coal 33%. However international gas markets are becoming tighter, coal isn't favoured because of co2 emmisions and climate change and our nuclear reactors are coming to the end of their working lives. Maintaining supply could well be problematic in the near future. I suspect there also political reasons. Continuing to be nuclear nation, both with energy generation and with weapons technologies gives us a seat at the top table in the international arena. Developing this technology does hold out the prospect of selling the technology to other countries who are also seeking ways to produce electricity while reducing co2 emmissions. But there are many problems.
If nuclear power was expanded globally to the level needed for it to be a solution to climate change then world stocks of uranium would last just 25 years. And how can we be seeking to profit from the technology while at the same time trying to restrict its use in Iran and other parts of the world we consider unstable or to be a challenge to our interests. Others have argued that if you look at the life cycle of nuclear generated electricity its not that clean anyway, even in terms of co2 emmissions. And what about the cost. Once upon a time nuclear power was going to provide electricity too cheap to metre. Whats actually happened is that billions of pounds of taxpayers money has been spent on R & D. That money has allowed the nuclear industry generate electricity at a price that gives the taxpayer no return on that investment and doesn't account for future decommissioning costs. Why would we want more of this. Especially when there is an alternative that could provide the 20%-30% of UK electricity needs, safely, cleanly and without the hidden and unspecified decommissioning costs that plague nuclear. Its time for a sea change in energy policy in the UK. Gordon, its time to go tidal.
Hydrogen Power and The Cars of the Future.
This week in London they've been holding the British International Motor Show. This year there's a Greener Driving Pavilion & Electric Vehicle Village. It would be nice to believe that the Motor Industry has suddenly decided to go green but mostly these things are driven by regulatory programs and as the EU in particular tightens rules on vehicle emissions, motor manufacturers are working hard to maintain market share. Manufacturers are also increasingly looking toward alternatives to petrol and diesel as power for their cars, hence the rise in hybrid cars, electric vehicles and hydrogen fuel cell technology.
Fuel cell technology seems to be where the motor industry is pinning its hopes for the future. Honda are the first company to have put a fuel cell powered car into production. Their FCX Clarity went into limited production this year (2008).
The claim commonly made for hydrogen fuel cell technology is that cars powered in this way are zero emissions cars, the hydrogen is converted into electricity with just water as a waste product. This claim is somewhat disingenuous. In the case of fuel cells hydrogen is not an energy source but an energy carrier. It takes considerable amounts of energy to produce the hydrogen in the first place. So while these cars and other electric vehicles may play a significant role in improving air quality in congested cities, the claim for zero emissions could only really be made if all the energy they consumed came from sources that produced no emissions. So is hydrogen fuel cell technology really going to allow us to keep using cars in the manner we've become accustomed to?
I'd like to answer yes. For all my interest in environmentalism and all things green I still love my car, I like the freedom it offers, its convenience and I'd find it hard to give up. But while hydrogen may offer solutions to specific transport problems the likelihood of it allowing us to maintain, as the motor manufacturers would like, a culture of mass car ownership seems remote. The problems are to great.
Large quantities of hydrogen are already produced for industrial use. Most of this is extracted directly from fossil fuels. In the USA 48% of hydrogen production comes from natural gas, 30% from oil, 18% from coal and jusy 4% from water electrolysis. Using hydrogen derived from fossil fuels to power cars is pointless. Its more efficient to simply power the car using fossil fuels directly. Besides, the idea is that hydrogen will replace oil as the motive power for cars.
The production of hydrogen by water electrolysis requires 50kwhrs per kg of hydrogen. High temperature electrolysis, possible making use of waste heat from nuclear power stations, could reduce the amount of energy required/kg dramatically. Even still to produce sufficient quantities of hydrogen to provide the energy equivalent of all the petrol we currently consume would require vast amounts of electricity. Then there's the fact that hydrogen is such a light gas. It is 2700 times less energy dense that petrol meaning that it needs to be compressed to be useful.
This compression requires energy, as much as 15% of the energy contained in the gas compressed to compress the hydrogen to 800 bars. At this pressure the hydrogen is still 3 times less energy dense than petrol and the steel tank needed to contain the pressurised gas would weigh vastly more than the gas it was holding. Currently the best fuel cells contain platinum and it seems unlikely that there is sufficient platinum to make sufficient fuel cells for us all to be using them in our cars.
In fact, as the technology stands today, simple rechargable batteries make far more sense as a means of powering cars. The widespread use of electric vehiles will increase demand for electricity and so increase the amount of generating capacity required. But the extra demands on electricity generating capacity be partially offset because most cars would be recharged at night when that capacity was not being utilised in other ways. For all this, moving away from oil as the transport fuel of choice without having to radically alter our transport use seems unlikely.
Tidal Power – A Technology Whose Time Has Come.
The UK has some of the best renewable energy resources in Europe and yet the best of them, tidal power, remains woefully underdeveloped. While the government has provided support for wind generated electricity the amounts spent developing wave and tidal power have been considerably smaller. This is a short sighted strategy.
The UK is a good place for wind power. It has 40% of Europes wind resource. But despite that there are days when the wind doesn't blow. What then? Government policy is for 15% of energy generation to come from renewable sources by 2020. With sources such as landfill gas and existing hydo-electric capacity forming a part of this 15%, the penetration of wind power into the UK supply remains small. What this means is that there is no need to build additional back up generating capacity. When the wind doesn't blow there is sufficient generating capacity from other existing sources (Nucleur, coal, gas etc) to keep supply within the grid constant. I've not been able to find figures that show to just what level wind power would have to penetrate the electricity market before it would be necessary to build balancing capacity to cover times when there is insufficient wind. Denmark is the world leader in exploiting wind power with 20% of domestic generation coming from wind. However this level of penetration of wind power is managed using connections to the grids of neighbouring countries allowing Denmark to draw extra power from elsewhere when it needs to. Given these obvious limitations why has the UK put so much money into wind power?
There are two main reasons. The first, not surprisingly, is cost. The capital cost of each windmill isn't that great and reducing all the time as the numbers built increases. The second and related reason is that with government targets on renewable energy relatively low, they can be met using cheap wind turbines without ever facing the prospect of disrupted supply or the need to build balancing capacity. Increase those targets and wind alone looks less like an answer. But the UK has not just great wind resources but also wave and tidal resources that as yet remain virtually unexploited. There is one wave powered generating plant of the Orkney Islands and no commercial tidal generated power at all.
The development of tidal power in the UK has been hampered by two things. The first has been the capital cost. Tidal power schemes have traditionally relied on barrages which are expensive to build and have large scale environmental impacts. The second has simply been difficulty. Why build at sea, underwater, when its so much easier to build on dry land. This second consideration is increasingly irrelevant as wind power moves offshore. While barrages remain the best option for many sites in the UK, for instance the Severn Estuary which has the second largest tidal range of any estuary in the world, the development of tidal generators by companies such as Blue Energy and Swan Turbines reduce both the initial capital cost and the environmental impact. Yet the development of tidal power remains woefully underfunded.
Its been estimated that the UK could generate over 30% of its electricity from tidal power despite the fact that only 3% of tidal power is in locations considered suitable for electricity generation and these figures could improve given sufficient money for research and development. While wave power shares with wind the problem of being unpredictable tidal power is as regular as the the moon revolving around the earth. It is this predictability that makes tidal power the most desirable of renewable energies and which makes its addition to the mix vital if the UK is to move beyond its very modest targets for renewable energy generation.
Peak Oil and Political Cowardice
Slowly, very slowly the term 'Peak Oil' is entering the publics' consciousness. That said were you to ask the average man in the street what the term meant you would in all probability be met with a blank stare. In terms of public recognition and political action Peak Oil seems to be where climate change was in the 1980s – which is nowhere. Yet Peak Oil offers challenges and threats potentially as great as those posed by climate change and those challenges and threats are probably more immediate than those of climate change
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Its A Big Subject
My name is Bruce Bell and I've been interested in environmental issues my entire adult life and most of these issues are at heart enegy issues. What else is climate change but a consequence of our use of fossil fuel energy? In fact over the past few years I've increasingly seen energy generation and use as being of central importance in tackling the environmental, economic and development challenges of the coming century. And energy is a huge subject
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