running a green office

energy - an overview

The western world’s energy watchdog has warned that the world will lurch from one energy crisis to another, unless governments switch from increased burning of fossil fuels to more nuclear, renewable and energy saving resources. The International Energy Agency (IEA) has forecast skyrocketing fuel prices, blackouts and supply disruptions as demand surges 50% in the next 25 years. The major problem with energy is that we are running short of traditional sources of supply; basically we have plundered the planet of coal, gas and oil to drive our development.

As sources dwindle (the world uses about 200 million barrels of oil every day and it may well run out in 40 years) demand for fuel rockets relentlessly. In addition climate change threatens the planet and we now have an energy crisis. This article looks at what fuels are available now, where the demand lies and what the alternatives for the future are.

More oil may be found, but it may be difficult to extract. Gas can replace oil but again that won’t last indefinitely and although there is plenty of coal around the world it causes high pollution. Chinese and Indian economic growth will propel global oil demand and it will be Saudi Arabia, Iraq and Iran that provide most of it. According to the IEA non-OPEC oil supplies will peak in the beginning of the next decade. When this happens, the IEA suggests that crude price could escalate to $130 per barrel. Carbon emissions may rise by more than 55%, accelerating climate change, and at the same time coal will become increasingly important. The United States, China and India have huge reserves of coal.

However, despite vast consumption of fuel one third of today’s world population has no access to electricity and another third have limited access. The western world consumes most of the world’s supply – the US has increased its oil use by almost 2.7 million barrels a day - but traditionally poor countries are catching up fast. China, for example wills double its demand for oil in 20 years. Developing countries need energy to improve their living standards and why should they be denied what the means to do so?

what fuels do we use?
Coal, mainly in power stations, covers about one quarter of our energy needs, but its use has declined since we have used more oil. Coal is the least efficient, unhealthiest and most environmentally damaging fossil fuel. New, cleaner extraction methods need to be found - there is probably about five times as much coal as oil.

Petroleum (derived from oil) provides around 40% of the world’s energy needs, mainly for cars. The US consumes around a quarter of all oil and generates a similar proportion of greenhouse gas emissions.

Oil mainly comes from the Middle East, which has half of all known reserves. Other significant sources include Russia, North America, Norway, Venezuela and the North Sea. There is oil in Alaska’s Arctic National Wildlife Refuge, but drilling is currently prohibited there, and if it were to be extracted one of the worlds last and most beautiful pristine wilderness would be devastated.

Opinions and estimates vary on when oil will run out. Most experts say we will exhaust easily accessible reserves within 50 years, but as demand outstrips supply in the next few decades an energy crisis could loom far sooner.

Burning fossil fuels has already released 400 billion tonnes of carbon into the atmosphere and it is estimated that burning the entire reserves could raise world temperatures by 13 degrees centigrade which would destroy the rainforests, melt all the Arctic ice and put London underwater.

Natural gas, which is the cleanest fossil fuel, will not last another 100 years, although it may be possible to access vast frozen methane hydrate reserves from beneath the sea bed in the future.

Hydrogen may become a key fuel in the future as it is a clean alternative for vehicles and is in abundant supply. But it needs vast amounts of energy, so until renewable energy is widely available for the process it is likely to remain on the sidelines.

nuclear power
Nuclear power is often sited as an answer, despite the facts that many environmentalists are deeply unhappy about extending an energy source which leaves a toxic legacy for hundreds of years. At present there are about 440 reactors in 32 countries which generate 16% of the world’s electricity. Accidents, terrorism, security and expense are obviously major concerns, although countries such as the US, Japan and India are shifting towards more nuclear energy use.

nuclear fusion
A new form of nuclear power which combines atoms rather than splitting them apart might be ready in thirty years time, but doesn’t answer today’s problems.

what are the alternatives?
The UK government estimates that 56% of energy used in UK homes could be cut using currently available technologies. In addition to energy conservation the most practical long-term energy solution appears to be using less pollutant, renewable energy sources. “Renewable” energy refers to the fact that these resources are not used faster than they can be replaced.

Hydroelectric power is the most common form of renewable energy, accounting for around one fifth of the world’s electricity, although there is still some controversy over its use. China’s Three Gorges Dam is the largest ever, with 26 turbines which generate the equivalent energy of 18 coal-fired power stations, yet this only equates to 3% of the country's current energy needs. Critics argue that the 600km project in some on China’s most scenic countryside forces the displacement of at least 1.3 million people and can contribute to greenhouse gases.

In 2003 Norway became the first country to harness tidal currents in the open sea for a commercial power station. Designed like an underwater windmill, this was the first of many new structures such as turbines, generators and floating pontoons that are now made from the power of the waves and the moon's gravitational tug. It is said that on an average day, 60 million square kilometres (23 million square miles) of tropical seas absorb an amount of solar radiation equal in heat content to about 250 billion barrels of oil.

Tidal energy is no easy answer; there are wide seasonal and geographic variations and, in most parts of the world, insurmountable difficulties. A Scottish company, Ocean Power Delivery Ltd (OPD) has developed a device that resembles a mechanical snake. Named after the sea snake, Pelamis, the red 450 foot long device floats though the waves and motion of the waves is converted into electricity through hinges hooked into electricity generators. The electricity is transmitted to the shore by cables.

The United States is seriously looking at tidal power, including utilising the tides in San Francisco Bay . Australia, the UK, Canada and many other countries are producing companies that want to harness the power of the moon and the sea.

Windpower has become the fastest growing type of electricity generation – quadrupling worldwide between 1990 and 2005. In fact, although it would be expensive, there is more than enough wind to provide the world’s energy needs.

Modern wind farms which consist of turbines that generate electricity are now fairly common sights. Windfarms are often in areas of natural beauty and are sometimes unpopular with locals. They can interfere with radar, alter climate, kill birds and frighten wildlife.

Scotland is building Europe’s largest wind farm which will power 200,000 homes. The world’s biggest wind farm will be located 12 miles off the coast between Margate in East Kent and Clacton in Essex. It will consist of 341 turbines spread over 90 square miles. The UK’s goal is to generate one fifth of power from renewable sources, mainly wind, by 2020. In the future we may see buildings with integrated turbines which may generate 20% of their own power, wind power used for shipping and floating wind farms.

solar power
Thermal solar power can directly heat water in rooftop panels for household supplies and sunlight can also be converted to electricity using photovoltaic cells, which use semiconductors to turn photons into electricity. Both types of power need good light. Solar panels can power spacecraft, cars and aeroplanes and when new cheaper versions of photovoltaic cells become available more energy could be generated from solar than from nuclear in the next 15 years.

nuclear fusion reactors
An international energy consortium has signed a formal agreement to build an experimental nuclear fusion reactor which aims to produce clean and limitless energy from nuclear reactions like those that fuel the sun. It is the biggest and most expensive scientific experiment since the space station.

The multi-billion euro project, which will be based in France, is hoped to produce electricity on the grid within 30 years. Known as Iter, or “on the way” the project involves the EU, South Korea, Russia, China, the US, India and Japan.

The green lobby is opposed to the project, believing the benefits have been oversold and the difficulties of waste production underplayed, and would prefer the money to be spent on proven projects. Others argue it is too expensive and will take too long.

Fans of the project argue that with the world’s energy due to increase by 60% in the next two decades and dwindling oil stocks, not to mention the fact that traditional sources of energy have on greenhouse gases and climate change, it is imperative to look at nuclear fission.

No-one underestimates the problems involved in imitating the fusion power of the sun. To initiate the fusion reaction hydrogen must be heated 10 times hotter than the core of the sun (to over 100 million Celsius, so the fuel particles can fuse. If these technical requirements can be overcome there are definite attractions – in particular the tiny amount of fuel needed. The release of energy from a fusion reaction is said to be 10 million times greater than from a typical chemical reaction such as burning a fossil fuel.

energy for vehicles
Biofuels. Ethanol is added to petrol in the US and millions of cars in Brazil also use it. Vegetable oils are already used in Europe to produce biodiesel. Soya oil could be used for aviations. Heat and electricity could be provided from fast-growing elephant grass or saplings and even sewage could be used as a biofuel. Hydrogen fuel cells have enormous potential but there are technical problems.

useful websites: British Hydropower Associations (BHA) British Photovoltaic Association (PV-UK) for information about solar energy in the UK and abroad.  British Wind Energy Association (BWEA) Combined Heat and Power Association (CHPA) Renewable Power Association Scottish Renewables

excellent sources of information include:  lots of facts, figures and latest information from the International Energy Agency.   New Scientist, an excellent site for in-depth information, news and articles.   look at the excellent Planet under Pressure series.  Energy Saving Trust. A group dedicated to promoting energy efficiency and the integration of renewable energy sources.   Carbon Trust. Organisation funded by the UK government to help business tackle their carbon emissions.  Centres for Alternative Technology (CAT),  Energy Saving Trust


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