– The energy sector has very long lead time. A nuclear power plant, for example, has a service life of over 40 years. So to modify the energy system, a long-term perspective is required. Therefore, policy makers need to make decisions today in order to affect the future. They need to understand where they want to head and how to get there, says Anna Krook Riekkola, Associate Senior Lecturer in Energy Engineering at Luleå University of Technology.
One way to explore different paths for the future is to use energy models such as TIMES. TIMES-Sweden is a complex optimization model with over 100,000 parameters that take into account technology, economy and environmental factors in the entire energy system, from energy supply to energy use in order to reach the demand for energy-related goods and services (e.g. km per person in a car, tons of produced steel, houses to be heated). The model helps decision makers to identify cost-effective ways to reach the given conditions and goals.
Technology development important to reach climate goals
The Government's climate goal is for Sweden to be carbon neutral by 2045. An ambitious goal! But it is possible to achieve if we continue to develop new and existing technologies. The scenarios created by TIMES-Sweden for instance assume that electric cars will become cheaper and that Carbon Capture and Storage (CCS) have been developed. CCS is a generic name for technologies where the carbon dioxide from a process are captured and stored deep in the ground or seabed.
– The model shows when in time different changes need to take place. This is important, because if actions are done in the wrong order, we may not reach the goals or it may become more expensive to reach the goals. The investments that are cheapest to cut the emissions by half could hamper the transition to net zero emissions, especially if those investments include a new infrastructure which may lock us in a certain technology path. TIMES-Sweden is dynamic which means that technology that is cheapest in the short term will only be selected if they also help to minimize the cost of reaching targets over the entire period.
The model shows that Sweden can convert to a carbon neutral energy system in 2045. Electricity, district heating and space heating can, in principle, be free of fossil fuels already in 2020. The challenge lies in the transport sector and in industry. For the transport sector, it is crucial to urge the technology development of fossil-free vehicles and biofuels, especially in terms of freight traffic. Some areas are more difficult to get carbon neutral, such as the cement industry, which releases carbon dioxide in certain processes, and then it does not help to change the fuel or technology. CCS can therefore be a solution.
Model that requires detective work
TIMES-Sweden is continuously updated; the model is a further development of a common European model that was developed in two different EU projects, where Anna Krook Riekkola was responsible for the Swedish part.
– TIMES-Sweden is adapted to Swedish conditions. We need to constantly update it with new information coming to light in reports and interviews. For example, biomass is an important part of Sweden's energy system, it is a limited resource that can be used in many different ways.
– One of the best parts of working with the model is that it requires some detective work. You may get a result that is a little unexpected. Then you have to go back and understand the chain of reactions that led to that result. It's also interesting to work with policy makers, and understand how they think. There are always those who will be very critical of the proposals I bring forward. Such a dialogue can lead us to update the model, but it may also be that those who are critical will have a difficult time to see the big picture because of the preference for a particular technology, says Anna Krook Riekkola.