Non-electric applications powered by nuclear energy offer increased energy efficiency and represent sustainable solutions for a number of energy challenges current and future generations will have to face. There is growing interest in increasing nuclear energy efficiency by using heat and other forms of energy generated by nuclear power plants as a by-product for seawater desalination, hydrogen production, district heating and various industrial applications. At a meeting at the IAEA last week, experts reviewed the status of harnessing this energy that would otherwise go to waste and dissipate as heat.
"Cogeneration could increase the overall thermal efficiency of a nuclear power plant by more than 30% by reusing waste heat and could decrease the environmental impact of heating and transport by up to 35%," said IAEA Senior Nuclear Engineer Ibrahim Khamis.
Nuclear power plants produce a large amount of both electricity and heat. Cogeneration merges the production of usable heat and electricity into a single process that can substantially reduce carbon emissions and energy costs. It is a more efficient use of fuel because otherwise wasted heat from electricity generation is put to productive use in district heating, desalination or hydrogen production.
Currently there are more than 70 nuclear power plants operating in cogeneration mode and the potential for applying this technology more widely appears promising, Khamis said.
Cogeneration benefits include:
Efficiency: Cogeneration requires less fuel than separate heat and power generation, to produce a given energy output. Cogeneration also avoids transmission and distribution loses that occur when electricity travels over power lines from central generating units.Reliability: Cogeneration can provide high-quality electricity and thermal energy to a site regardless of what might occur on the power grid, decreasing the impact of outages and improving power quality for sensitive equipment.Environmental impact: Because less fuel is burned to produce each unit of energy output, cogeneration reduces emissions of greenhouse gases and other air pollutants.Economic benefits: Cogeneration can save facilities considerable money on their energy bills due to its high efficiency, and it can provide a hedge against unstable energy costs.