Human activity is making the planet warmer. (Image source: SXC)
Global warming is one of the greatest challenges humanity has ever faced, and urgent measures are necessary to stop it from happening. (Do you want to learn more about global warming? Check out these links).
There is a lot we can do to stop global warming. We need to replace as much fossil energy as possible with renewable alternatives, and we need to replace fossil fuels in our cars with renewable fuels. We have to stop cutting down rain-forests, too, and we need to conserve energy. In addition to this, we need to capture and store CO2. These are the most important reasons why:
- We use so much fossil energy that it will take many decades to replace it all with renewable alternatives. In fact, the world energy consumption is likely to increase in the nearest decades, because world population is growing and more people are leaving poverty and demand the same commodities as we have in places like Europe and the USA.
- A relatively small number of emission source are responsible for a very large portion of the total global emissions. That means a relatively small number of CCS plants can cut global emissions by a very large share.
- Some emissions can't be removed any other way. Certain industrial processes, such as the manufacturing of cement and steel, emit great amounts of CO2. In fact, a fifth of all CO2 emitted comes from industrial processes, and while some of these processes can be improved or replaced to reduce emissions, these emissions can't be completely eliminated as long as we need the products they produce.
- We have no time to lose. Carbon capture and storage means we can start removing CO2 right now, from power plants and industrial plants that already exist and that we know will continue emitting CO2 for decades to come. Opportunities like this can not be ignored when climate action is so urgently needed to save the planet.
Oil refinery. (Image source: SXC)
More than half of the global emissions of greenhouse gases come from the use of oil, coal and natural gas. There is no way we can stop climate change unless we drastically reduce these emissions. So the obvious solution is to stop using fossil fuels. So why don't we?
Because we use a lot of fossil fuels. A lot. In 2007, we used about 115 000 TWh worth of it. That number may not mean much to you, unless you're really into these things, so let us put it into perspective: If we were to build enough wind turbines to replace all this fossil energy, it would take approximately 50 million new turbines. If you started building now, one new turbine every minute, it would take almost 100 years to finish. We don't have that kind of time.
So until we've built enough wind turbines, hydro-power plants, solar panels and other renewable alternatives, we will continue using fossil fuels. In fact, as the global population grows, and as the poorer countries in the world develop and begin demanding the same kinds of comforts as we enjoy in Europe and the USA, the use of energy will increase, making replacing fossil fuels quickly even harder.
This is the Sasol Secunda fuel plant in South Africa. It's the largest emission source in the world, emitting 57 million tons of CO2 a year. That is more than the entire emissions of the country of Norway. (Image source: SXC)
Large emission sources
There are hundreds of millions of emission sources in the world. However, most of them are quite small. You wouldn't capture the CO2 from your gas heater. Instead you replace it with electricity from a renewable source, or you change from fossil gas to renewable bio gas. However, of these millions of sources, there are a few that are a lot bigger than the others. These are the ones we need to capture and store CO2 from.
The 2000 largest CO2 point sources in the world account for 40 percent of the total global emissions. That makes CCS a potentially very effective way of achieving considerable cuts in emissions. Some of these emission sources literally emits as much CO2 as a small country.
Also, quite often large sources of CO2 are clustered together within a small geographical area, making them even better suited for CCS, as they can share some of the infrastructure, like using the same pipelines to transport the captured gas and sharing storage locations.
Production of cement is a large source of CO2 emissions. (Image source: SXC)
Most people don't think of concrete as a source of pollution. But production of cement is actually one of the greatest industrial sources of CO2 in the world.
The thing is, cement is made from limestone or chalk - natural minerals that contain carbon, calcium and oxygen. To make cement, you remove some of the oxygen and most of the carbon in a process that involves heating the limestone until the carbon is released as CO2. At present there are no practical alternatives to this process.
There are only two ways of stopping this CO2 from entering the atmosphere. Either we stop making cement, or we capture the CO2 and store it. Most people would agree that the first solution is not an option, so CCS remains the only alternative for these emissions.
This is not the only industrial process that emits CO2. Production of steel is another huge emitter of CO2. So is the production of important chemicals such as ammonia and methanol.
The largest emission sources in the world. (Image source: IPCC)
We have no time to lose
Cutting greenhouse gases is becoming increasingly urgent, as it becomes ever clearer how dramatic the consequences will be if we don't. That means we can't afford not using the solutions we have available to us. CCS alone will not remove all emissions. But it can take a large share, and in combination with renewable energy, energy conservation and other climate change mitigation solutions, it can make a very big difference. For all these reasons, we need carbon capture and storage.
Want to learn more?
About global warming
- Met Office: Climate change — your essential guide A nice Introductory guide to climate change provided by the UK National Weather Service.
- NASA's Eyes on the Earth - Lots of information on climate Change from NASA
- Intergovernmental Panel on Climate Change Collection of IPCC reports, if you really want to get into the depths of it.
- Global waming on Wikipedia A good starting point to find more detailed information on global warming. Fairly accurate information, but may contain erroneous or misleading information, so use with care.