Towards zero greenhouse gas emissions: energy efficiency and demand reduction key

How can we reach zero greenhouse gas emissions by 2050? According to Professor Ernst Worrell, a completely sustainable energy supply is a major challenge. This is in large part due to a potential lack of raw materials if energy demand keeps rising. Solutions such as Carbon Capture and Storage may not be rolled out in time. We must therefore first focus on increasing the economy's resource and energy efficiency, and reduce demand as much as possible.

Ernst Worrell is Professor of Energy, Resources & Technological Change at the Copernicus Institute of Sustainable Development, Utrecht University, where he focuses on industrial energy and material efficiency improvement. He heads the Industry, Innovation & Infrastructure (SDG 9) and Responsible Consumption and Production (SDG 12) themes.

Carbon neutral by 2050: starting now and with already available technology

“To have an impact, it is important that any technology to reduce carbon emissions is ready to use now and entirely scalable. It is too late to halt carbon emissions in 2049 to be carbon neutral by 2050,” says Worrell. “The earlier we start with the transition the better for future generations”.

Progress across many sectors

According to Worrell there is already a lot at our fingertips. The technology exists to seasonally store heat and run greenhouses and farms on geothermal or solar energy, and what’s on offer in terms of meat alternatives its growing every day. Electric cars will play a crucial role in rethinking the way people move around and cities will increase their density and expand their public transport systems. Worrell admits that transport that cannot easily be electrified poses a challenge. “Biofuels could definitely play a role here, but that is not enough. We need to reduce demand. Flying to Barcelona for 25 euros shouldn’t even be possible. And why are trains so expensive? Transport needs to be fairly taxed so that cleaner modes of transport are given priority”.

Flying to Barcelona for 25 euros shouldn’t even be possible. And why are trains so expensive? Transport needs to be fairly taxed so that cleaner modes of transport are given priority.

The challenge of high temperature industrial processes

Most industry can be powered by low or zero carbon sources. Material producing industrial processes, however, require very high temperatures. High temperatures can only be generated by concentrated energy, which is difficult to achieve with renewable energy. This resulting reliance on fossil fuels means that industries such as steel, cement and chemicals are responsible for a large chunk of global emissions. “To continue producing them using coal would mean rolling out CCS on a large scale, which may not be feasible at the scale needed in the thirty year time frame until 2050,” explains Worrell. “This leaves two other options”.

More recycling

“We need a sustainable circular economy that is more efficient with how it uses materials and resources. Using less and recycling more. We can then reduce the need for high temperature processes. What’s more, there is more and more available to recycle. We have used so much steel to build up our society that there is currently about 10-12 tonnes of it for every person. Steel is recycled with electricity, which is about 70% more energy efficient than making it from scratch”.

Increasing efficiency

“Some say there will soon be so much steel scrap that there will be no need to continue production. I disagree with this. Aside from corrosion losses, the quality of scrap steel is often poor and there is increasing demand for high quality products”.

Technologies are being developed to make iron with far less energy and carbon dioxide emissions. This includes HIsarna, where iron ore is processed almost directly into liquid iron or hot metal. There is a HIsarna pilot plant at Tata Steel in IJmuiden, The Netherlands. Another example is Hybrite. Here reduced iron is directly produced using hydrogen from electrolysis using renewable power, with a pilot plant under construction in North Sweden.

“But to have an impact by 2050,” says Worrell, “development and implementation must be quick and we are not there yet. Both industry and policymakers are struggling to address this innovation gap. A blast furnace typically runs for 50-60 years. Technologies to replace current blast furnaces must be scaled up very quickly to replace those close to retirement”.

Outlook for a carbon neutral 2050

“We should have started thinking about the energy transition many years ago. The problem is that society fails see problems in the long term. There needs to be a collective vision of what the future will look like. We also need to understand that what we’re doing now will drive us off the cliff. It will not only have huge consequences for future generations, but also for us. A carbon neutral 2050 will require policies some people don’t like. There is an urgent need to think about how we can sell actions necessary for the survival of our children and future generations”.

A carbon neutral 2050 will require policies some people don’t like. There is an urgent need to think about how we can sell actions necessary for the survival of our children and future generations.

About Ernst Worrell

Ernst Worrell is an internationally recognized expert on industrial energy efficiency. From 1998 until 2008, he led the industrial energy assessment work at Lawrence Berkeley National Laboratory. Between 2004 and 2010 he was Director of Energy Use and Efficiency at the sustainable energy consultancy Ecofys. He was a visiting scientist at Princeton University (USA) in 1994-1995, and a visiting professor at the Universidade de Sao Paulo, Brazil in 1996. Worrell is author of four IPCC (The Intergovernmental Panel on Climate Change) reports, including Coordinating Lead Author for the Industry Chapter of the Fourth Assessment Report: Climate Change 2007, making him a Laureate of the Nobel Prize for Peace 2007.