Clean energy is energy gained from sources that do not release air pollutants, while green energy is energy derived from natural sources. There is a subtle difference between these two energy types even though they are often spoken of as being the same.
Renewable energy is power generated from sources that are constantly being replenished. These renewable energy resources won’t run out, unlike fossil fuels and gas, and include wind and solar energy.
However, while most green energy sources are renewable, not all renewable energy sources are seen as being green. For example, hydropower is a renewable resource, but some would argue that it is not green, since the deforestation and industrialization related to the building of hydro dams can damage the environment.
The perfect clean energy mix occurs where green energy meets renewable energy, such as solar energy and wind energy.
An easy way to remember the differences between these different energy types is:
- Clean energy = clean air
- Green energy = natural sources
- Renewable energy = recyclable sources
Clean energy works by producing power without having negative environmental impacts, such as the release of greenhouse gases like carbon dioxide. A lot of clean energy is also renewable, including wind power, some hydro resources and solar-powered energy generation.
The most important aspect of clean energy is the environmental benefits as part of a global energy future. While clean, renewable resources also preserve the world’s natural resources, they also reduce the risk of environmental disasters, such as fuel spills or the problems associated with natural gas leaks. With fuel diversification, through different power plants using different energy sources, it is possible to create reliable power supplies to enhance energy security, ensuring there is enough to meet our demands.
Clean energy provides a variety of environmental and economic benefits, including a reduction in air pollution. A diverse clean energy supply also reduces the dependence on imported fuels (and the associated financial and environmental costs this incurs).
Renewable clean energy also has inherent cost savings, as there is no need to extract and transport fuels, such as with oil or coal, as the resources replenish themselves naturally.
Other industrial benefit of a clean energy mix is the creation of jobs to develop, manufacture and install the clean energy resources of the future.
Clean energy can be used for a variety of different applications, from electricity generation to heating water and more, depending on the source of the energy.
Solar energy can be used for heating and lighting buildings, generating electricity, heating water directly, cooling and more. Solar panels allow for energy from the sun to be collected and turned into electricity. Solar panels are frequently used for small electric tasks, such as charging batteries, while many people already use solar energy for small garden lanterns. However, this same clean energy technology can be scaled up to larger panels that are used to provide power for homes or other buildings or even installations of multiple solar panels, such as with a community solar panel array to power entire towns.
Water is another clean resource with some surprising applications. Most obvious are hydroelectric power plants, which take the flow of water from rivers, streams or lakes to create electricity. A less obvious use of water comes through municipal pipes in towns and cities. With lots of water running through pipes in homes each day, there is a move towards harnessing this energy to help meet domestic and other power needs. As generators become smaller and less expensive to build this use of municipal water is becoming closer to being a daily reality.
Wind power works by attaching a windmill to a generator which turns the turning of the windmill blades into power. This form of energy has been used for centuries to grind grain, pump water or perform other mechanical tasks, but is now being used more often to produce electricity. Onshore and offshore wind farms are becoming increasingly prevalent, but wind power can also be used on a much smaller scale to produce electricity, even to provide a source of power for recharging mobile telephones.
These examples of renewable sources can be added to by others, such as geothermal, biomass and tidal power, which also all have their own benefits and applications.
The future of clean energy looks bright, with recent years showing that more renewable energy capacity has been installed globally than new fossil fuel and nuclear capacity combined. Renewable sources now make up over one-third of globally installed power capacity. As an example of this growth, Wednesday 10 June 2020 marked two months of the UK being powered purely by renewable energy for the first time ever.
As the world population continues to grow, there is an ever-increasing demand for energy and renewable sources are the answer to providing sustainable energy solutions, while also protecting the planet from climate change.
The take-up of clean energy is not just happening on a national level as cities and states are also creating policies to increase renewable energy use. In the United States, 29 states have set renewable energy portfolios to mandate that a certain percentage of energy consumed should come from renewable sources, and over 100 cities around the world now use at least 70% renewable energy. As more cities drive towards becoming 100% renewable, corporations are also playing a part by purchasing record levels of renewable power.
Of course, due to fossil fuels being a finite resource, it makes sense that the future is renewable and so it is expected that renewable sources will continue to increase in number, driving down the cost too.
Humans have been using fossil fuels for over 150 years and, as their use increased, so did the release of the greenhouse gases that are produced when these fuels are burned. These greenhouse gases trap heat in the atmosphere causing the temperature of the Earth to rise. This global warming is one symptom of climate change that has seen a rise in extreme weather events, shifting wildlife habitats and populations, rising sea levels and other impacts.
Because renewable energy sources don’t emit greenhouse gases such as carbon dioxide, they do not contribute to global warming. These renewable sources mean that climate change is not being advanced, while measures such as reforestation can help to alleviate the damage already done to the climate, combining to reduce global warming.
As mentioned above, humans have been using fossil fuels for decades, meaning that the switch to clean energy has been relatively recent. As a result, renewable energy sources are still seen as being unpredictable and do not yet meet our global power demands. This means that renewable energy is still being topped up with carbon-based energy sources.
However, it is believed that our energy needs can be balanced by the efficient storing of renewable energy so it can be used when the demand is present. A great deal of work is being done to improve the infrastructure and storage capabilities of clean energy, with experts saying that clean renewable energy could replace fossil fuels by 2050.
There are financial benefits related to clean energy, not least due to the creation of work to improve the infrastructure, manufacture clean energy solutions and install and maintain them. Renewable and clean energy are growth sectors as the world begins to move away from fossil fuels, meaning that more opportunities will arise in areas ranging from eMobility to power generation and storage.
The expertise that comes with developing these next-generation power solutions can be of benefit to those that attain it, offering work and contracts to those who are slow to take up clean energy.
Of course, the financial implications of clean energy are just part of the story, since the real incentive behind clean energy is creating a better future for the planet. But, as fossil fuel use declines, so will the associated financial rewards, meaning that clean energy is not just good for the environment but it is a forward step for the industry too.
Clean energy can be obtained from a variety of sources which, when put together, could create solutions for all of our energy needs.
- Sunlight is the most abundant and freely available energy resource on the planet, in fact, the amount of solar energy that reaches the Earth in one hour is enough to meet the total energy requirements for the planet for an entire year. Of course, solar power is limited by the time of day, the seasons of the year and geographical location. Despite this, solar energy is being used on both a large and a domestic level already.
- Wind power is another plentiful source of clean energy, with wind farms providing a good contribution to power in the UK and elsewhere. As of yet, while domestic ‘off grid’ wind energy is available, not every property is suitable for a wind turbine.
- Hydro or water power is one of the most commercially developed sources of clean energy. This energy source is seen as more reliable than either wind or solar power and also allows for the easy storage of the energy that is generated so it can be used in line with demand. Municipal hydropower is also being investigated, meaning that the future could see us all using the flow of water through pipes in our homes to generate electricity. Tidal power is a large-scale version of hydropower and, although it doesn’t provide a constant supply of energy, it is highly predictable and reliable.
- TWI has been involved in a great deal of work to advance geothermal power, which harnesses the natural heat below the Earth’s surface. Used to heat homes or generate electricity, this resource is more effective in some regions than others. Iceland, for example, has a plentiful and easily reachable geothermal resource, while geothermal heat in the UK, by comparison, is far less freely available.
- Biomass uses solid fuel created from plant materials to produce electricity. Although this energy source still requires the burning of organic materials, this is not wood and is now much cleaner and energy efficient than in the past. Using agricultural, industrial and domestic waste as solid, liquid and gas fuel is not only economical but also has environmental benefits too.
All clean energy sources are, by definition ‘clean,’ however not all renewable energy sources are clean. For example, burning wood from sustainably managed forests can be renewable, but it is not clear since this releases carbon dioxide into the atmosphere.
To be truly clean the carbon cost of production and storage needs to be zero, and this is where sources such as solar power and wind energy are seen as being truly clean and renewable.
Clean energy appears to be the future for the power needs of humanity across the globe as the reliance of fossil fuels continues to diminish. As the drive towards clean, green and renewable energy continues to advance, the cost will fall and work will be created to develop and install these new power solutions.
More and more people are recognizing the environmental, societal and economic benefits of clean energy and, as more cities, states and nations sign up to a green power agenda, this will continue to advance.