Cars are bad. Much pollution. Kills environment.

In previous years, the vast majority of fuel was coming from non-renewable resources, such as oil, natural gas, and coal. Using these sustainably was never a problem until our society began to exponentially rely on fossil fuels for fuel. Depletion of these resources became rapid. In todays society, we are still heavily reliant on fossil fuels but with limited remaining the price is beginning to rise and territorial wars are occurring over fossil fuels. With this being said, scientists are looking at more sustainable renewable resources. Such as wind power, wave power, solar power etc…

Applying this to heat engines is important because most heat engines are built on the principle of combusting fuel which is obtained from fossil fuels. There needs to be a development on finding an alternative which can replace fuel (obtained from non-renewable resources) and replace it with a renewable fuel. Many attempts have been made however any new renewable fuel put forward has had significantly less efficiency than the non-renewable counterpart.

Moreover, when fossil fuels are burned, they release carbon dioxide and other greenhouse gases. Too much carbon dioxide and/or greenhouse gases causes ozone depletion. This is very dangerous and causes global warming.

Overall, heat engines, need to be developed to be more sustainable and ran on renewable resources which have less of an environmental effect. However, the biggest drawback is efficiency.

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