Sustainable energy use

SDG Ensure access to affordable, reliable, sustainable and modern energy for all

Increasing demand for energy

There are several inter linked factors contributing to our ever increasing use of energy. One is our growing population which is unlikely to stabilise before 2050 and at a total of 9 billion people. Contrast this with the world’s population 100 years ago which was around 2.0 billion. Another factor is our own individual use of energy which has increased dramatically in developed countries since the start of the industrial revolution in the home and at work.

Our major uses of energy include transport, generation of electricity and providing space and water heating in buildings. If we define energy as the capacity for doing work then we have developed machines over a period of many years to do the work that was previously done by hand. The energy that these machines consume has been provided primarily by coal, oil and gas and it is in the combustion of these fossil fuels that greenhouse gases like carbon dioxide are produced as a by-product.

Greenhouse gas emissions emerging from industrial chimneys (Jan Smolik)

? Why has our energy usage increased over the past 100 years? What usage do you think is making the greatest contribution to global warming? 

Reducing environmental impact of energy use

There are 3 basic ways in which we can reduce the environmental impact of our energy use –

• Using less energy
• Using energy more efficiently
• Converting our energy sources from fossil fuels to renewable sources; we have considered these sources and noted how they can be used around our home in the renewable source section

As renewable energy sources are characterised by a large initial cost and low running cost, it is always cost effective to consider how to use less energy and use it more efficiently before converting an energy source to a renewable source.