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Geothermal and industrial heat demand – new IEA report on the role of heat

Industrial heat demand, IEA report (source: screenshot/ IEA)
Alexander Richter 10 Nov 2017

A new report by IEA highlights the incredibly important role of industrial heat demand in the climate change discussions and the role of renewables in this context ... somewhat neglecting the great role geothermal energy could play.

In a report published in October 2017, the International Energy Agency (IEA) highlights the important role of heat in the future energy market.

Reducing long-term greenhouse gas (GHG) emissions of the industry sector is one of the toughest challenges of the energy transition.

Combustion and process emissions from cement manufacturing, iron- and steelmaking, and chemical production are particularly problematic. This report considers a variety of current and forthcoming options to increase the uptake of renewables as one possible way to reduce industry sector energy and process carbon dioxide (CO2) emissions.

The main finding of this report is that the recent rapid cost reductions in solar photovoltaics (PV) and wind power may enable new options for greening the industry, either directly from electricity or through the production of hydrogen (H)-rich chemicals and fuels. Simultaneously, electrification offers new flexibility options to better integrate large shares of variable renewables into power grids.

What is though interesting, the report completely neglects the possible role of geothermal energy.

In the above picture, one can see the incredibly important role of heat in the context of energy demand.

Industrial emissions play an important role and are often not considered in the discussions on a shift from fossil-fuels to renewable energy sources. Under different climate change estimates, the share of direct CO2 emissions from industry will increase considerably and “three industries delivering basic materials – cement, iron and steel, and chemicals – are responsible for 70% of all global direct industrial CO2 emissions today (75% with the addition of the aluminium and pulp and paper industries).”

“These emissions result from the combustion of fossil fuels for energy purposes and from process emissions, notably from hydrogen manufacturing, limestone calcination in cement production, and iron ore reduction in steelmaking. These emissions result from the combustion of fossil fuels for energy purposes and from process emissions, notably from hydrogen manufacturing, limestone calcination in cement production, and iron ore reduction in steelmaking.

Three-quarters of the energy used in industry is process heat: the rest is for mechanical work and electricity (computers, lighting, etc.). About 30% of process heat is “low-temperature” (below 150°C), 22% is “medium-temperature” (150°C-400°C) and 48% is “high temperature”(above 400°C) (Figure 3, see above). About 10% of process heat is estimated to be electricity-based.

So there is a tremendously large part of the energy demand or at least 30% that could be covered by lower heat geothermal resources with temperatures below 150 degrees Celsius. Combined with medium-temperature resources geothermal could play a rather positive role.

Unfortunately, this is not discussed in the report by IEA.

Source: IEA, “Renewable Energy for Industry – from green energy to green materials and fuels” (report, pdf) and Solar Paces