Tag: FAQs (frequently asked questions)

What is carbon capture usage and storage?

21 August 2020

Carbon capture
Carbon capture

What is carbon capture usage and storage?

Carbon capture and storage (CCS) is the process of trapping or collecting carbon emissions from a large-scale source – for example, a power station or factory – and then permanently storing them.

Carbon capture usage and storage (CCUS) is where captured carbon dioxide (CO2) may be used, rather than stored, in other industrial processes or even in the manufacture of consumer products.

How is carbon captured?

Carbon can be captured either pre-combustion, where it is removed from fuels that emit carbon before the fuel is used, or post-combustion, where carbon is captured directly from the gases emitted once a fuel is burned.

Pre-combustion carbon capture involves solid fossil fuels being converted into a mixture of hydrogen and carbon dioxide under heat pressure. The separated CO2 is captured and transported to be stored or used.

Post-combustion carbon capture uses the addition of other materials (such as solvents) to separate the carbon from flue gases produced as a result of the fuel being burned. The isolated carbon is then transported (normally via pipeline) to be stored permanently –  usually deep underground – or used for other purposes.

Carbon capture and storage traps and removes carbon dioxide from large sources and most of that CO2 is not released into the atmosphere.

 What can the carbon be used for?

Once carbon is captured it can be stored permanently or used in a variety of different ways. For example, material including carbon nanofibres and bioplastics can be produced from captured carbon and used in products such as airplanes and bicycles, while several start-ups are developing methods of turning captured CO2 into animal feed.

Captured carbon can even assist in the large-scale production of hydrogen, which could be used as a carbon-neutral source of transport fuel or as an alternative to natural gas in power generation.

Key carbon capture facts

Where can carbon be stored?

Carbon can be stored in geological reserves, commonly naturally occurring underground rock formations such as unused natural gas reservoirs, saline aquifers, or ‘unmineable’ coal beds. The process of storage is referred to as sequestration.

The underground storage process means that the carbon can integrate into the earth through mineral storage, where the gas chemically reacts with the minerals in the rock formations and forms new, solid minerals that ensure it is permanently and safely stored.

Carbon injected into a saline aquifer dissolves into the water and descends to the bottom of the aquifer in a process called dissolution storage.

According to the Global CCS Institute, over 25 million tonnes of carbon captured from the power and industrial sectors was successfully and permanently stored in 2019 across sites in the USA, Norway and Brazil. 

What are the benefits of carbon storage?

CO2 is a greenhouse gas, which traps heat in our atmosphere, and therefore contributes to global warming. By capturing and storing carbon, it is being taken out of the atmosphere, which reduces greenhouse gas levels and helps mitigate the effects of climate change.

Carbon capture fast facts

  • CCUS is an affordable way to lower CO2 emissions – fighting climate change would cost 70% more without carbon capture technologies
  • The largest carbon capture facility in the world is the Petra Nova plant in Texas, which has captured a total of 5 million tonnes of CO2, since opening in 2016
  • Drax Power Station is trialling Europe’s biggest bioenergy carbon capture usage and storage project (BECCS), which could remove and capture more than 16 million tonnes of CO2 a year by the mid 2030s, delivering a huge amount of the negative emissions the UK needs to meet net zero

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What is the national grid?

Power generation
Electricity grid

What is the grid?

The national grid, or simply the grid, is the network of powerlines, pylons, gas lines and interconnectors that makes up Great Britain’s electricity and gas systems — and the engineers, technology and rules responsible for their seamless operation. It ensures electricity generated anywhere, by any source, can be transmitted to meet the demand for power wherever it’s needed across the country. It heats homes and businesses. It helps us to cook our food.

The national electricity grid consists of a high voltage transmission system, which connects electricity from power stations to substations and smaller local networks – called Distribution Network Operators, or DNOs – which transport electricity into homes and businesses.

Key national grid facts

How does it work?

Transporting electricity around the grid is more complicated than just connecting cables to power generators. In order to move power around the country, things like voltage and frequency of electricity must be balanced and kept uniform at all times. Without this, unstable electricity could damage equipment and ultimately lead to blackouts.

The National Grid Electricity System operator (ESO) is a separate entity from the National Grid company, and is responsible for maintaining the correct voltage, frequency and reserve power levels to ensure electricity is transmitted safely and efficiently at all times.

It does this by working with power generators and energy storage facilities to provide what are known as ‘ancillary services’ – a set of processes that keep the power system in operation, stable and balanced.

The national grid is the network of power stations, powerlines and electricity infrastructure that allows electricity to be generated, transported and used across the country.

Who controls it?

In Great Britain the National Grid company owns and operates the transmission systems which ensure electricity is delivered safely and reliably across the country.

The local distribution system is made up of 14 regional DNO companies, which deliver electricity at a lower voltage from substations to homes and businesses.

Great Britain’s grid incudes England, Scotland, Wales and several surrounding islands. Northern Ireland is part of an island-wide electricity system with the Republic of Ireland.

National grid fast facts

  • Great Britain’s grid is made up of more than 7,000 kilometres of cables, 90,000 pylons, 346 substations, and 1,500 kilometres of underground cables
  • Construction of the grid began on 14 July 1928 and was completed on 5 September 1933
  • It was originally designed to operate as 7 separate, connected grids, before a group of rebellion engineers attempted to run it as one on 29 October 1938. It has run as one grid ever since
  • A decade ago, Britain had 80 individual points of generation to manage. Today there are nearly one million
  • All electricity in Great Britain operates at a frequency of 50Hz. A deviation of just 1% above or below could cause damage

How is the grid changing?

As the sources that generate Great Britain’s electricity change to include more renewables, the grid has also changed.

The grid was built to work with large power stations that operate huge spinning turbines. With decarbonisation it’s evolved to include a greater variety of intermittent weather dependent sources such as wind, solar and decentralised power sources that serve individual buildings or communities.

This makes managing the grid’s stability more complicated, and requires the use of more ancillary services, usually delivered by flexible generators such as thermal power stations.

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What is climate change?

Sustainable business
Climate change

What is climate change?

Climate change refers to the change in weather patterns and global temperature of the earth over long periods of time. In a modern context, climate change describes the rise of global temperatures that has been occurring since the Industrial Revolution in the 1800s.

What causes climate change?

While there have been natural fluctuations in the earth’s climate over previous millennia, scientists have found that current-day temperatures are rising quicker than ever due to the excessive amount of carbon dioxide (CO2) and other greenhouse gasses being released into the atmosphere.

Key climate crisis facts

An excess of CO2 in the atmosphere accentuates something called the ‘greenhouse effect’. As CO2 traps heat in the earth’s atmosphere, it warms the planet and causes a rise in average global temperature. International efforts, such as the Paris Climate Accords, are dedicated to ensuring temperatures do not rise 2 degrees Celsius above pre-industrial levels, which could lead to catastrophic conditions on the planet.

In the modern context, climate change describes the rise of global temperatures occurring since the Industrial Revolution in the 1800s.

How do humans contribute to climate change?  

Industries such as transport, agriculture, energy and manufacturing have traditionally relied on the use of coal, oil and other fossil fuels. These fuels, when combusted or used, emit large amounts of CO2 into the atmosphere, further advancing the greenhouse effect and contributing to climate change.

Human reliance and consumption of these products mean today CO2 levels are the highest they’ve been in 800,000 years.

Why are rising temperatures harmful to the planet?

Our planet has a history of experiencing periods of extreme weather conditions – for example the last Ice Age, which finished 12,000 years ago. However, the rapid rise in temperatures seen today is harmful because a hotter planet completely affects our natural environment.

A steep rise in global temperature can melt ice sheets and cause higher sea levels which can, in turn, contribute to more extreme storms and even threaten entire islands and coastal communities. As the planet warms, extreme weather events, such as bushfires could become more common, which can destroy homes, impact agriculture and degrade air quality, while entire ecosystems, habitats and animal and insect species could also be threatened by climate change. 

What can be done to mitigate the effects of climate change?

Reducing CO2 emissions is a key way of slowing down the pace of climate change. To do so, industries across the global economy must decarbonise to become less dependent on fossil fuels, such as coal and petrol, and adopt new lower carbon energy sources.

Decarbonisation will rely on a number of factors, including a technological response that sees the development and implementation of carbon neutral and carbon negative ways of creating heat, electricity and fuels, including the use of innovations such as carbon capture and storage (CCS).

There is also a need for a policy and governmental response that promotes investment in new cleaner technologies and disincentivises dirtier industries through mechanisms like the carbon tax. Countries and economies will need to work collaboratively to achieve common, climate-oriented goals that will also enable smaller scale action to be taken by individuals around the world. 

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What are ancillary services?

Power generation
Ancillary services

What are ancillary services?

Ancillary services are a set of processes that enable the transportation of electricity around the grid while keeping the power system operating in a stable, efficient and safe way.

Why do we need ancillary services? 

When electricity makes its way through the country, it needs to be managed so that the power generation and electricity useage levels are equal.

The regulating of elements such as frequency and voltage has to be carefully managed, so that the massive amounts of electricity moving – or transmitted – are able to be used safely in homes,  businesses, schools and hospitals around the country.

Ancillary services enable the power system to operate in a stable, efficient and safe way.

 What do ancillary services offer?

Ancillary services include a wide variety of electrical efficiency and safety nets, all focussed on ensuring the power system delivers enough output to meet demand yet remains stable:

Frequency: The UK’s power system runs at a frequency of 50 hertz – to stay balanced, it has to remain at that frequency. Turbines and generators adjust the speed at which they spin automatically to increase or decrease power in line with demand and ensure that the system is kept stable.

Voltage: Different parts of the UK’s transmission system use voltages of either 400, 275 or 132 kilovolts. To ensure that voltage remains within 5% of those figures at all times, to be safe for domestic electricity use, power stations can produce or re-absorb excess energy as reactive power, keeping the overall system reliable.

Inertia: Turbine use is important in keeping the system operating in its current state, even with disruptions and sudden changes. The electricity system uses the weight of heavy spinning turbines to create stability, acting as dampeners and smoothing out unexpected changes in frequency across the network.

Reserve: An important part of ancillary servicing is making sure that there are no surprises – so holding back powerto release if something unexpected happens means that the network can function confidently, knowing that there are generators and other power providers such as pumped hydro storage waiting ready to back it up.

Key facts about ancillary services

Who manages ancillary services?

In the UK the grid’s stability is managed by National Grid Electricity System Operator (ESO) – a  separate company of National Grid Electricity Transmission (ET). The ESO works with ancillary service providers to either sign long-term contracts or make short term requests for a service.

These partners are often power stations, such as Drax Power Station, which have large spinning turbines capable of controlling voltage, frequency, providing inertia and serving as a source of reserve power. 

What is the future of ancillary services, as we move to a more renewable system?

As the UK’s electricity system continues to change, so to do its requirements for different ancillary services. The switch from a few very large power stations to a greater variety of different electricity sources, some of which may be dependent on the weather, as well as changes in how the country uses electricity, means there is a greater need for ancillary services to keep the grid stable.

These services have historically been delivered by thermal power stations, but new innovations are enabling wind turbines to provide inertial response and overcome changes in frequency, and batteries to store reserve power that can then be supplied to the power system to ensure balance.

Ancillary Services

Ancillary services fast facts  

  • Batteries can in some cases be cheaper ancillary alternatives to conventional sources of energy. The Hornsdale Power Reserve, which runs on a Tesla battery in South Australia, lowered the price of frequency ancillary services by 90% after just four months of use.
  • Ancillary services usually work from habit; knowing when to slow electricity production, or increase supply based around the general public’s standard working hours, dinner time and the early morning rush.
  • But during the COVID-19 lockdown, electricity consumption on weekdays fell by 13% and so National Grid ESO had to intervene with ancillary services to keep the lights on.
  • Every year, the ESO’s ancillary services move 300 terawatt hours (TWh) of electricity, which is equal to 4 trillion kettles boiling at once.

With recent innovations around renewable energies, there are a wider variety of ways for ancillary services to generate power.

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What is reforestation and afforestation?

Sustainable bioenergy
Reforestation and afforestation

What is reforestation and afforestation?

Reforestation is the process of planting trees in a forest where the number of trees has been decreasing.

Afforestation is when new trees are planted or seeds are sown in an area where there were no trees before, creating a new forest.

Why carry out reforestation and afforestation?

Reforestation and afforestation are two of the leading nature-based solutions for tackling the effects of climate change. For commercial foresters and landowners, these two practices are essential to ensuring they can grow wood for wood products and continuously meet demand in a sustainable way.

Reforestation is crucial in combating or preventing deforestation or forest degradation, where forests shrink in size or are completely removed. As well as reducing a forest’s ability to absorb carbon dioxide (CO2), deforestation can destroy wildlife habitats and contribute to the likelihood of flooding in certain areas.

Afforestation can also help avoid desertification, where fertile land turns into a desert as a result of drought or intensive agriculture.

Reforestation is the process of planting native trees in a forest where the number of trees has been decreasing.

How does reforestation and afforestation limit the effects of climate change?

Forests are a natural way of keeping the earth’s CO2 levels in check. The more trees there are, the more CO2 is captured and converted into oxygen through photosynthesis.

By absorbing CO2, forests help to lower the amount of greenhouse gasses in the atmosphere and reduce the effects of climate change.

Reforestation and afforestation help maximize these abilities of forests by increasing the overall amount of forested land on the planet.

Key forest facts

Did you know?

Different types of forests, such as tropical, swamps or mangroves, all absorb CO2 at different rates.

The age of a forest also impacts absorption. Young, rapidly growing, trees absorb CO2 at a faster rate than more mature ones, which have large amounts of carbon locked in already.

Afforestation is when new trees are planted or seeds are sown in an area where there were no trees before.

What roles does reforestation play in commercial forestry?

The global wood products industry depends on sustainable forests to supply the wood needed to make furniture, create construction materials and provide fuel for energy.

The supply chain will often start with what’s called a ‘working forest’ – a commercially-run forest which is often privately owned. The landowner will grow a working forest to a certain stage of maturity and then harvest some or all of the trees to sell the wood. Once the wood has been sold for use as lumber, wood products or fuel, the landowner will reforest the areas to regrow the trees.

Foresters will typically do this in stages across their land to ensure there are multiple stands of forest at different stages of growth across their land, which ensures there is consistent, sustainable growth at all times.

Fast facts

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What is decarbonisation?

Carbon capture
Decarbonisation

What is decarbonisation?

Decarbonisation is the term used for the process of removing or reducing the carbon dioxide (CO2) output of a country’s economy. This is usually done by decreasing the amount of CO2 emitted across the active industries within that economy. 

Why is decarbonisation important?

Currently, a wide range of sectors – industrial, residential and transport – run largely on fossil fuels, which means that their energy comes from the combustion of fuels like coal, oil or gas.

The CO2 emitted from using these fuels acts as a greenhouse gas, trapping in heat and contributing to global warming. By using alternative sources of energy, industries can reduce the amount of CO2 emitted into the atmosphere and can help to slow the effects of climate change.

Key decarbonisation facts

Why target carbon dioxide?

 There are numerous greenhouse gases that contribute to global warming, however CO2 is the most prevalent. As of 2018, carbon levels are the highest they’ve been in 800,000 years.

The Paris Agreement was created to hold nations accountable in their efforts to decrease carbon emissions, with the central goal of ensuring that temperatures don’t rise 2 degrees Celsius above pre-industrial level.

With 195 current signatories, economies have begun to factor in the need for less investment in carbon, with the UK leading the G20 nations in decarbonising its economy in the 21st century.

How is decarbonisation carried out?

There are numerous energy technologies that aim to reduce emissions from industries, as well as those that work towards reducing carbon emissions from the atmosphere.

Decarbonisation has had the most progress in electricity generation because of the growth of renewable sources of power, such as wind turbines, solar panels and coal-to-biomass upgrades, meaning that homes and businesses don’t have to rely on fossil fuels. Other innovations, such as using batteries and allowing homes to generate and share their own power, can also lead to higher rates of decarbonisation. As the electricity itself is made cleaner, it therefore assists electricity users themselves to become cleaner in the process.

Other approaches, such as reforestation or carbon capture and storage, help to pull existing carbon from the air, to neutralise carbon output, or in some cases, help to make electricity generation – and even entire nations – carbon negative.

Alternative power options means that homes and businesses don’t have to rely on traditional carbon fuels.

What is the future of decarbonisation?

For decarbonisation to be more widely adopted as a method for combating climate change, there needs to be structural economical change, according to Deloitte Access Economics. Creating more room for decarbonisation through investing in alternative energies means that “there are a multitude of job-rich, shovel-ready, stimulus opportunities that also unlock long-term value”.

 Decarbonisation fast facts

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