An energy crisis is any great bottleneck in the supply of energy resources to an economy. It usually refers to the shortage of oil and additionally to electricity or other natural resources. An energy crisis may be referred to as an oil crisis, petroleum crisis, energy shortage, electricity shortage or electricity crisis.Market failure is possible when monopoly manipulation of markets occurs. A crisis can develop due to industrial actions like union organized strikes and government embargoes. The cause may be over-consumption, ageing infrastructure and sometimes bottlenecks at oil refineries and port facilities restrict fuel supply. An emergency may emerge during unusually cold winters.Pipeline failures and other accidents may cause minor interruptions to energy supplies. A crisis could possibly emerge after damage from severe storm. The British 2005 oil terminal fire and shortages due to Hurricane Katrina were mostly remediated quickly causing only minor fuel shortages. Attacks by terrorist on important infrastructure are a potential problem for energy consumers, with a successful strike on a Middle East facility potentially causing global shortages. Political events, for example, when governments change due to regime change, monarchy collapse, military occupation, and coups can disrupt oil and gas production and create shortages.The macroeconomic implications of a supply shock-induced energy crisis are large, because energy is the resource used to exploit all other resources. When energy markets fail, an energy shortage develops. Some scientists sure that we are in an energy crisis and we will have to do something quickly. Fossil fuels (coal, oil and gas) are rapidly running out. The tragedy is that fossil fuels are far too valuable to waste on the production of electricity. There are so much thinks we can do from oil. If we don't start conserving these things now, it will be too late.An electricity shortage is felt most by those who depend on electricity for their heating, cooking and water supply. In these circumstances a sustained energy crisis may become a humanitarian crisis. Although technology has made oil extraction more efficient, the world is having to struggle to provide oil by using increasingly costly and less productive methods such as deep sea drilling, and developing environmentally sensitive areas such as the Arctic National Wildlife Refuge.The world's population continues to grow at a quarter of a million people per day, increasing the consumption of energy. The per capita energy consumption of China, India and other developing nations continues to increase as the people living in these countries adopt more energy intensive lifestyles. In response to an energy crisis the principles of green energy and sustainable living movements gain popularity. This has led to increasing interest in alternate power/fuel research such as fuel cell technology, liquid nitrogen economy, hydrogen fuel, biomethanol, biodiesel, Karrick process, solar energy, geothermal energy, tidal energy, wave power, and wind energy, and fusion power.To date, only hydroelectricity and nuclear power have been significant alternatives to fossil fuel. Hydrogen gas is currently produced at a net energy loss from natural gas, which is also experiencing declining production in North America and elsewhere. When not produced from natural gas, hydrogen still needs another source of energy to create it, also at a loss during the process. This has led to hydrogen being regarded as a 'carrier' of energy, like electricity, rather than a 'source'.To the mind of some scientists the nuclear power is the only real alternative. We are getting some electricity from nuclear power-stations already. If we invest in further research now, we'll be ready to face the future. There's been a lot of protest lately against nuclear power -some people will protest at anything — but nuclear power-stations are not as dangerous as some people say. It's far more dangerous to work down a coal-mine or on a North Sea oil-rig. Safety regulations in power-stations are very strict. If we spent money on research now, we could develop stations which create their own fuel and burn their own waste. If you accept that we need electricity, then we will need nuclear energy. It’s difficult to imagine what the world would be like if we didn't have electricity — no heating, no lighting, no transport, no radio or TV. Other type of explorer consider the nuclear energy is expensive, dangerous, and evil, and most of all, absolutely unnecessary. We have some reasons to doubt the nuclear energy is an efficient way of producing energy. There is no perfect machine. Machines fail. People make mistakes. A serious nuclear accident must be inevitable — sooner or later. Huge areas would be evacuated, and they could remain contaminated with radioactivity for years. People won't get a penny in compensation. No insurance company covers nuclear risks. Radioactivity causes cancer and may affect future generations. Next, nuclear waste. There is no technology for absolutely safe disposal. Some of this waste will remain active for thousands of years. Next, terrorism. Terrorists could hold the nation to ransom if they captured a reactor. There are also some optimists who note that if we listened to the pessimists none of us would sleep at night. More oil and gas is being discovered all the time. In the short-term, we must continue to rely on the fossil fuels -oil, coal and gas. But we must also look to the future. Our policy must be flexible. Unless we thought new research was necessary, we wouldn't be spending money on it. After all, the Government wouldn't have a Department of Energy unless they thought it was important. The big question is where to spend the money — on conservation of present resources or on research into new forms of power.