Eco FAQs

The terms used to describe environmental issues can be confusing. So, we've compiled our own FAQs to help you tell your carbon sinks from your hybrid cars.

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Biodiversity:

The variety of animal and plant species found within a particular place.

Is global biodiversity affected by climate change?

Studies have highlighted a steady decline in biodiversity across the globe in recent decades, with some estimating that one in eight plant species are now threatened with extinction.
Deforestation, urbanisation and pollution are major culprits, but climate change may equally play a part. Warmer temperatures have for instance allowed exotic animals and plants to settle in temperate areas, sometimes threatening native species.

Biofuel:

A liquid or gas fuel made from plant material or waste. Biofuels could constitute an alternative to fossil fuels such as oil for transportation.

Are biofuels a realistic substitute for oil?

Concern about carbon emissions and soaring oil prices have made biofuels an increasingly attractive option. But despite their environmental credentials, they could be accompanied by problems of their own.
Rising demand is predicted to make growing crops for biofuels more profitable than food production. Some therefore fear that this will cause lower food production and consequently higher food prices, with poorer countries being hit hardest. Biofuels could equally promote deforestation as fields are cleared for new crops.
What’s more, biofuels may not be as environmentally friendly as they appear. Intensive agriculture, processing and transporting fuel to consumers all generate carbon emissions, reducing the overall benefits of the biofuels produced.
This does not mean that biofuels will never be a viable alternative to oil, but these issues will need to be considered carefully before biofuels hit the mass market. Second generation biofuels, still in development, promise to extract energy from waste, addressing some of critics’ major environmental concerns.

Carbon capture and storage (CCS)

A proposed means of cutting the amount of CO₂ released into the atmosphere by capturing CO₂ emissions from large sources, such as power plants, and storing them underground.

Will carbon capture and storage provide a feasible means of reducing fossil fuel CO₂ emissions?

One third of the UK’s CO₂ emissions emanate from power stations, so carbon capture and storage has great potential to cut down on our carbon footprint.
The new technology could indeed strip down a power plant’s carbon emissions by up to 90%.
The capture process is relatively straightforward, but research is still being carried out into determining the best means of storing the gas. CO₂ could be injected into underground geological formations including old oil fields, or locked up inside minerals such as serpentine which act as CO₂ sponges.
 Whilst this technology is still at an experimental stage, you can expect to hear a lot more about it in years to come.

Carbon emission

The release into the atmosphere of CO₂ and other greenhouse gases, typically caused by the burning of fossil fuels.

Why does burning fossil fuels release CO₂?

Carbon is the basic building block forming all living organisms. Fossil fuels are made from fossilised plant material and are therefore constituted mainly of carbon. Under the right temperature and pressure conditions, ancient vegetation is transformed into gas, oil or coal, in a process lasting millions of years. Combustion occurs when carbon inside fossil fuels reacts with oxygen, generating heat as well as CO₂ and water. Other gases and particles in the air produce side reactions, leading to the formation of other gases such as nitrogen oxides (NO_x).

Carbon footprint

The quantity of carbon emissions caused by an individual, organisation or process. This is usually measured in tons of carbon or of CO₂.

Why is CO₂the most powerful greenhouse gas?

The simple answer is that it isn’t – water vapour accounts for up to two thirds of the natural greenhouse

effect. Human activity however has very little effect on the water vapour content of the atmosphere, but fossil fuel combustion is estimated to have increased CO₂ concentrations by 37%. CO₂ still makes up a tiny fraction of the atmosphere – about 0.0038% - but is particularly harmful because it remains in the atmosphere for a long time. It is equally twice as powerful as the second most potent greenhouse gas – methane. Scientists therefore blame CO₂ for 55% of manmade global warming.

Carbon neutral

A product or process which overall does not cause greenhouse gas emissions, either because it doesn’t involve burning fossil fuels or because its emissions are offset.

Is it possible for me to be carbon neutral?

Leading an entirely carbon neutral existence would require many lifestyle changes. This could include such measures as: switching to a renewable energy provider, making one’s household energy efficient, becoming a vegetarian (meat production generates many more carbon emissions), recycling, travelling exclusively by foot, bike or electric car... Even then, there would inevitably be remaining emissions which could be offset – if you were to purchase an electric car, for example, its manufacture would inevitably have caused greenhouse gas emissions. As technology advances, it should however become easier to reduce our impact on the environment. And when fossil fuels eventually run out, we will have no choice but to be carbon neutral. In the meantime, there are plenty of things you can do to cut down on your personal carbon footprint.

Carbon offsetting

A means of compensating for greenhouse gas emissions by financing projects which will take up an equal amount of CO₂. Examples include planting trees (which absorb CO₂) or funding environmentally sustainable schemes in developing countries.

Is carbon offsetting a good way of limiting my environmental impact?

Carbon offsetting is an increasingly popular way for individuals and organisations to reduce their carbon footprint. Offsetting funds projects can reduce deforestation and also encourage sustainable development in poorer countries.
Critics however argue that offsetting emissions merely enables people to clear their consciences and carry on polluting as before. Its effectiveness is equally contested, as there is no regulation of companies selling offsets and therefore no real guarantee that emissions will really be compensated for.
Measures such as planting trees are useful only if the trees are cared for indefinitely – if they die, the carbon they sequestered during their lifetime will be released back into the atmosphere as they rot.
In sum, carbon offsetting may help to mitigate your environmental impact, but to make a real difference, it is far preferable to burn less fossil fuels in the first place.

Carbon sink

Any process, activity or mechanism that results in the removal of CO₂ from the atmosphere. Oceans and forests are the two largest carbon sinks.

How can the ocean’s capacity as a carbon sink be increased?

The oceans make up the world’s largest carbon sink, soaking up a third of manmade CO₂. Much of this is actually taken up by phytoplankton, microscopic plants living in the upper waters. It has been suggested that the ocean’s capacity as a carbon sink could be expanded by ‘fertilising’ the oceans with iron.
Phytoplankton need iron to grow, but this metal is hard to come by in the ocean, limiting the plankton numbers and therefore the total amount of carbon they can remove from the atmosphere. Trials have shown that adding iron to the water boosts phytoplankton populations, which take up more CO₂ as their numbers increase. The wider consequences of iron fertilisation  are however unknown and will need to be investigated before this technology can be applied on a larger scale.

Climate change

Variation in the Earth’s climate over time, with many recent changes attributed to human activity. Predicted climate change will lead to warmer global temperatures, a rise in sea levels and changes in rainfall patterns.

How will climate change affect the UK?

Climate science is still in its infancy, scientists cannot therefore ascertain exactly what impacts climate change will have. Across the globe, the effects of climate change are likely to be felt in many different ways.
Predictions for Britain however include higher sea levels, increased rainfall and storms, milder winters and hotter summers. Wetter weather and higher sea levels may increase the likelihood of floods, but water shortages are also probable in the summer.
Changes in weather conditions are equally likely to have an impact on British wildlife. Warmer temperatures may for instance make our country more hospitable to species from continental Europe, but could reduce the ranges of native species adapted to colder conditions.

Fossil fuels

Fuels obtained from fossil carbon deposits such as oil, natural gas and coal. Their combustion results in the emission of greenhouse gases.

Can nuclear power reduce our reliance on fossil fuels?

Nuclear power is a contentious issue, with environmental concerns supporting both sides of the argument.

Nuclear power stations do not produce carbon emissions, but they do generate radioactive waste. If not properly disposed of, this waste could be hugely damaging to human health as well as natural ecosystems.
A quarter of the UK’s power currently comes from nuclear energy, but most of the country’s nuclear reactors are due to close within the next 20 years. Renewable energy sources could fill the gap left by nuclear power, but the government has been advised that if the UK is to meet its carbon emission targets, more nuclear power plants will need to be built.

Fuel cell

A device producing electricity by converting hydrogen and oxygen into water. This is done without releasing any greenhouse gases or other pollutants.

Will fuel cells soon be widespread?

Fuel cells are one of the most promising green technologies to have seen the light of day. But for the time being, they remain costly and are also relatively inefficient, which has limited their use. Many commercial companies have nonetheless invested in hydrogen fuel cell technology, and researchers are confident that they can improve existing prototypes. It is therefore expected that in future, fuel cell powered cars, spacecraft and electronic devices will become commonplace.

Greenhouse effect

The trapping of heat from the sun by gases in the Earth’s atmosphere. The greenhouse effect occurs naturally – without it average global temperatures would hit a chilly -18C. The phenomenon has, however, been exacerbated by manmade emissions, causing climate change.

How does the greenhouse effect actually work?

Radiation from the sun, mainly in the form of visible light, travels through the atmosphere. It powers processes such as photosynthesis and equally heats the earth’s surface. However, as the ground warms, some of this energy is reflected as longwave – or infrared – radiation, which is absorbed by greenhouse gases, heating the atmosphere. The strength of the greenhouse effect is therefore dependent on the concentration of greenhouse gases present in the atmosphere.

Greenhouse gas

A gas which contributes to the greenhouse effect, locking up heat in the atmosphere. Greenhouse gases include carbon dioxide (CO₂), water vapour, methane (CH₄) and nitrous oxide (N₂O). Such gases are released when fossil fuels are burnt.

If ozone is a greenhouse gas, then why should we be worried about the hole in the ozone layer?

The functioning of the atmosphere is very complex and the same gas can be responsible for numerous different effects. Ozone is not emitted by fossil fuel combustion, but forms in the lower atmosphere when sunlight breaks down pollutants such as hydrocarbons and nitrogen oxides. At ground level, ozone is harmful to human health and is considered to be a damaging pollutant. Higher up in the atmosphere, ozone acts as a greenhouse gas, trapping heat.
However, in small quantities ozone is beneficial, as it filters out harmful UV radiation. Ozone depletion, as observed above Antarctica in the 1980s, could therefore lead to a rise in skin cancer rates and possibly harm wildlife. Chemicals known as CFCs, which were the major cause of ozone depletion, are now banned and the ozone layer is making a steady recovery. 
Sufficient quantities od ozone to shield us from UV rays are produced naturally in the higher layers of the atmosphere, environmentalists are therefore more concerned with avoiding excess ozone production caused by air pollution.

Hybrid vehicle

A vehicle using two or more energy sources. The term usually refers to hybrid-electric vehicles, which contain both an internal combustion engine and an electric motor.

What makes hybrid cars environmentally friendly?

Transport is currently a major source of greenhouse gas emissions on our planet. Hybrid-electric vehicles however promise a greener future, combining a conventional engine and an electric motor.
Hybrids still consume fossil fuels but at a much lower rate. The average CO₂ output for a UK car is 170-200 g/km, but hybrids can virtually halve this, achieving 105 g/km.
This is mainly thanks to the vehicle’s electric motor. Although they are usually powered by electricity generated from the car’s fuel, electric motors make much better use of this energy. Many can even recapture energy when braking or travelling downhill. The electric motor is used continuously, with the petrol engine only kicking in at high speed. As a result, although the car is powered by petrol, it uses it in the most efficient way possible.

Renewable energy

Energy derived from renewable sources, such as wind power or solar energy.

Can renewables alone meet the world’s power needs?

As our planet’s fossil fuel reserves dwindle, we will have no choice but to switch to renewable energy sources. Renewables currently provide only 14% of the world’s energy, but, fortunately, their capacity could be vastly expanded. Exploited to their maximum potential, renewables could supply several times the estimated global energy demand in 2100.
The world’s largest offshore wind farm will soon be under construction in the Thames estuary and is set to cover a third of London households’ electricity demands.
Many renewable technologies such as solar power remain costly relative to fossil fuel combustion, but improved efficiency and government subsidies could soon make them competitive.

Solar panel (or photovoltaic cell)

A device that converts the sun’s energy into electricity or heat. Photons, the particles which make up light, are absorbed by the cell, knocking electrons off its silicon atoms and producing an electrical current.

Will solar power work in the UK?

Solar power captures the energy from the sun’s radiation. The UK is however notorious for its rainy weather, so is solar power an effective solution for it to meet its energy needs?
Thankfully, solar cells do not need direct sunlight to produce electricity or heat water– the diffuse light filtering through clouds is enough. In our country a solar water-heating system can supply between 80 and 90 per cent of a household’s hot water in summer, between 40 and 50 per cent in spring and autumn and between 10 and 15 per cent in winter.

Wind turbine

A machine used to convert wind energy into electrical power. Functioning in a similar way to a windmill, the wind sets the turbine’s blades into motion, powering an electricity generator.

Are wind turbines harmful to birds?

Concerns are often raised by the potential threat which wind turbines may pose to birds. However, such claims are frequently based on relatively old studies. Modern, more efficient turbines actually spin slower than older models, and can usually be avoided by birds, some of which have even be known to nest on top of turbines.
Whilst turbines do inevitably claim occasional casualties, by avoiding sensitive sites, such as migration routes, the problem can be largely avoided. Furthermore, many bird species could suffer from the impacts of climate change which wind farms could help to mitigate.
Most experts therefore agree that, all in all, wind farms are a good thing for birds and the environment as a whole.

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