I’ve spent the best part of my professional career working at the nexus of business, environment and energy. Finding ways to develop energy sources which do not result in an environmental liability and make good business sense so that they can be implemented in a way which makes a positive impact. The need for energy in our modern society is fundamental. Its beyond question. Our society is built on the use of energy and it is entwined within the very fabric of our society and economy.
However, the environment is also entwined. Environmental degradation is accelerating at an increasingly alarming rate. Many believe we are in a state of crisis. Future generations are already holding us accountable for what we do – or don’t do.
Within this narrative there is the question of how energy can be produced and used. The arguments made around how energy efficiency plays into this are not covered here. That is for a future article. What I do want to cover is the environmental effect of different sources of electricity.
First, its important to realise that all forms of energy production have an environmental impact. Some have a greater impact. All energy generation will lose some energy in mechanical generation and to heat and all forms of energy transmission will lose energy during this transportation process. Thus, no form of energy production is completely efficient.
What follows is a very high level and brief overview of some of the environmental effects of different electricity generating sources:
On the surface this looks like the ideal energy solution. Plants absorb carbon dioxide. They regrow so are renewable. Their cultivation supports landowners and employees. Unfortunately, its not that easy. Plants take a lot of energy to grow and to then process into fuel. The debate around ethanol production impacts verses carbon offsets is ongoing.
Although it causes fewer polluting emissions than, say, coal, biofuels do produce carbon dioxide and sulphur when burned. Indeed, emissions are the key point of contention here. I have been involved in consenting a biomass power station as well as an energy from waste plant. Emissions were by and far the greatest challenge we had both from a technical and a perceptual perspective.
There is also the issue of waste generated from burning. Ash can contain some very harmful and toxic residue which has often been mobilised by high heat in burning. This toxic residue must be disposed of and this is often in landfill.
In terms of ethanol, this is often added to gasoline and it does produce a cleaner gasoline. However, the additives lead to increased smog, ozone problems and it still results in carbon dioxide emissions. Biodiesel does produce less sulphur oxide, carbon monoxide and hydrocarbons than traditional diesel but it does lead to increased nitrogen oxide emissions.
Despite the US Presidential love affair with coal, it has the potential to do massive harm to air, water and land. Acidic water run off, disposal of mining waste, carbon emissions from plant use and coal transport as well as the emissions and waste from using coal to generate electricity have all resulted in coal use declining in many Western countries as a major fuel source for generating electricity. Other countries such as the US, China and some other Asian countries still use coal extensively.
Geothermal produces relatively little environmental impact. No fuel is burned. They do create relatively few emissions usually in the form of carbon dioxide and sometimes sulphur. I was recently involved in a deep well geothermal development dispute in Africa and the key environmental impact was in the use of water during drilling. This as significant and if not sourced and managed properly, this can be a significant issue. However, this was a short term and temporary situation whilst the bore holes were being drilled. It is wise to be mindful of this impact though as it can lead to significant local stress for people, plants and agriculture if not
identified and managed properly.
This is a favourite form of renewable energy production. In Scotland, a whole industry was built on it post World War II. However, although there are no emission issues with hydro, there are issues of water course impacts, impacts on fish populations, sediment blocking and changes in water temperature, flow and distribution. Technologies such as fish ladders help. However, the presence of dams does change migration patterns and thus impact fish populations.
Petroleum (Oil and Gas)
This is oft bashed industry by environmentalists. Good environmental governance is often seen as a response to legislation and to shareholder pressure rather than an intrinsic drive to make the world a better and greener place. However, many companies do make as little impact as possible considering their operations. Chemicals used to stimulate well production are as environmentally sound as possible. Sites must be restored to their former condition post operation as well.
One key concern has always been oil spills. Events such as Deepwater Horizon further elevate concerns. However, most spills seem to occur in transportation and transfer both in tankers and pipelines. Many factors play into this – aging technology, political upheaval, civil unrest, storms and other high intensity weather events.
Ultimately, these fuels are burned, and this process will always produce carbon dioxide, carbon monoxide and other air pollutants. Whether this happens as a result of driving a car, powering a generating station or producing electricity to charge EV’s, the emissions still happen.
There are no emissions form this technology in the production of electricity or transfer of heat. The key pollutants here are form the mining of materials to manufacture component parts of the system – precious and rare metals etc. also, in certain climates, the use of water to clean concentrators and receivers may cause a negative effect.
Uranium (Nuclear Energy)
At the point of producing electricity, there is no carbon generated / released and no air pollution. For some reason, many governments – including the UK Conservatives – deem this to be renewable.
However, nuclear does produce harmful by-products. Many of these are items which have come into contact with low levels of radioactive material. These are known as low level waste and strict regulations are in place to govern how they are handled and transported. Spent fuel is highly radioactive and must be processed at specialist facilities.
The issue is what to do with this waste. It will be radioactive and harmful for thousands of years. Currently, ‘Best Practice’ is to dig a hole in the ground and bury it reasoning that future generations can deal with it. As well as this, nuclear uses huge amounts of water to cool reactors. Often nuclear plants are built at coastal locations to use sea water for this. This results in a build-up of salts and other toxic material often discharged into the sea creating radioactive hot-spots. On a longer-term front, building these facilities on the coast is short sighted as it makes no allowance for rising seal levels or for natural disaster events such as
Wind (Onshore and Offshore)
Wind is clean, it creates no air pollution and no water pollution. Nothing is burned. Early concerns around bird and bat mortality are proving to be unfounded. The greatest impacts are argued to be those of carbon release from peat bogs on which onshore wind farms are often located. However, lifecycle assessments are showing that the payback in terms of comparing to coal or gas powered generation is positive. The greatest impact from wind is arguably the visual impact. That is a strictly a personal perception as many polls show people who live near onshore wind farms don’t find them visually offensive.
This is by necessity a high-level overview of the area. I’d be really keen to hear reader views on what they consider to be key impacts. As for the best source of power, I’ll leave that to your own judgement.