Study asks – ‘What if all of Paris were air-conditioned using geothermal energy?’

Source:ThinkGeoEnergy – Geothermal Energy News
Original URL:https://www.thinkgeoenergy.com/study-asks-what-if-all-of-paris-were-air-conditioned-using-geothermal-energy/

A study published by the French Association of Geothermal Professionals (AFPG) analyzes the benefits of widespread deployment of geothermal air-conditioning solutions, specifically using the city of Paris as an example. The study finds that, over 50 years, close to EUR 1 billion in long-term value can be derived if all of Paris were air-conditioned using geothermal energy when compared to other widely adopted solutions for cooling.

The full report “Study on the role of geothermal energy in air-conditioning and cooling” (in French) can be accessed via this link.

The growing need for air-conditioning

Factors like climate change, urbanization, and poorly designed buildings are causing the demand for air-conditioning to grow, even in regions where air-conditioning traditionally had a very small share in energy consumption. France is one of the countries affected by this phenomenon. Despite initiatives to build more green spaces in cities, more and more households and buildings are resorting to installing cooling systems.

The penetration rate of air-conditioning in France has reached 25% as of 2020, accounting for about 4 to 5 TWh of energy consumption per year. This number is expected to grow to 12 TWh by 2050. In the tertiary sector, about 40% of buildings have installed air-conditioning, contributing to 11 TWh of energy consumption per year.

Air-conditioning using geothermal energy is thus proposed as an alternative to more traditional methods. By expelling heat in the subsurface, geothermal air-conditioning helps avoid the urban heat island affect caused by excessive heat dissipation to the atmosphere. Beyond this natural advantage the study seeks to quantify the long-term economic benefits of adopting geothermal air-conditioning technologies.

Cost-benefit analysis for geothermal air-conditioning

The analysis covers five different building typologies (single house, networked housing, office building, shopping center, facility for elderly care), as well as different technical scenarios (vertical geothermal probes and geotherm energy on aquifers). However, the study notes that are other solutions available such as compact or horizontal heat exchangers.

Analyses done in all scenarios indicate significant savings compared for geothermal air-conditioning compared to conventional solutions. For instance, a geothermal probe solution becomes more cost-effective than a gas boiler and air-conditioning system after 13 years. In a networked system, the geothermal solution becomes more cost-effective after only y years.

The city of Paris was used as an example for the analysis to better appreciate the scale of savings from geothermal air-conditioning. The air-conditioning demand of Paris is expected to increase to 3.5 TWh/year in the coming years. With the “Fraîcheur de Paris” network already supplying around 456 GWh/year of cooling, the scenario assumes that the rest of the air-conditioning demand will be supplied by geothermal solutions.

Considering the costs of installing geothermal air-conditioning systems (50% vertical probes, 50% aquifer-based), as well as the multitude of benefits from lower operational costs, reduced mortality and hospitalization, reduced productivity loss, and reduced carbon emissions, implementing geothermal air-conditioning in Paris over the 25 years has a net present value of EUR 874.37 million. It is considered a profitable venture with a cost-benefit ratio of 1:1.13.

The study makes an important contribution to improving the understanding of the role of geothermal energy in air-conditioning. It can be improved with more accurate data, the study presents highly positive trends and prospects.

Source: AFPG