Adjustable nuclear power to stabilise generation and distribution of electric power

Nuclear power is often considered a rigid production form. This perception is based on the traditional practice of running nuclear power plants at full capacity throughout the year. This is due to the cost structure of nuclear power and the constant steady need for general power. Nuclear fuel is affordable.

However, the fact is that it is easy to adjust the output of nuclear reactors within an extensive power range. German Isar 2 nuclear power plant holds the record among currently running plants in adjustability. The reactor's nominal output is 1,400 megawatts, and it can be adjusted in a range of 400−1,400 megawatts, with an adjustment speed of 40 megawatts per minute. The need for this great an adjustment capacity has resulted from Germany's current energy policies.

Unleashed adjustment potential lies hidden in currently running nuclear power plants.  A specific value must be set for adjustment capacity, so that adjustments to a nuclear power plant's output could realistically spur business. Adjustment of a nuclear power plant's output also means that there is a need for research that will determine the usability and safety of plants.

Amount of electricity consumed must also be produced

New nuclear reactor types are entering the power plant market. They combine a plant size that can be flexibly adopted, good adjustability, as well as a high standard of safety and a resource-efficient fuel economy. Flexibility in plant size ranges from approximately 50 to 500 megawatts.

The same amount of electricity that is consumed must also be produced for the national grid. Otherwise there will be disruptions in electricity distribution and, this in turn, will seriously hinder our way of life. Electricity consumption in the grid varies according to the time of day and time of year, because we work during the daylight hours and vacation during summer. Storage technology that is of an industrial-scope and steering of consumption help balance the worst peaks during each day, but the key rule is that electricity production must be adjusted according to variances in consumption.

The decentralised electricity production system adopted last year in Germany sees production vary randomly according to the weather and regularly according to season.

 For this reason, the German power system requires adjustable power for balancing more than ever before, and nuclear power has become a significant stabilising part in the country's electricity system.

Finland has been foresighted

Finland has exhibited wisdom in the long-term with regard to its decision to build national electricity distribution based on production methods that complement one another. In the 2020s, nuclear power's share of total power production will rise to around 40 per cent. This will effectively cut Finland's carbon dioxide emissions. The system still has plenty of room for both old and new renewable energy forms.

It remains to be seen, what type of investments are made in renewable energy. Old carbon-neutral, renewable energy forms, especially biomass will continue to be used in Finland. However, production of biomass may change as industry goes through structural changes.

New nuclear reactor types offer new types of business opportunities in the form of decentralised nuclear power. At the same time, they also create a need to develop currently used licensing and decision-making procedures. This area offers an abundance of room for pioneering, multidisciplinary work out of the box.

Further information:

Professor Juhani Hyvärinen, tel. +358 50 524 1512, juhani.hyvarinen@lut.fi