Every year in France, thousands of megawatt-hours of heat are produced… and then wasted. According to ADEME (the French Agency for Ecological Transition), the total potential of waste heat from industry and municipal waste incineration plants (MWIPs/WWWs) amounts to 117.9 TWh per year. This considerable energy is often dissipated into the air or water, when it could be used locally to heat public buildings, homes, or supply urban heating networks.
What is fatal heat?
Waste heat refers to the thermal energy lost during industrial, commercial, or urban processes and not recovered . It can originate from:
- waste incineration plants ,
- wastewater treatment plants ,
- data centers,
- or even building cooling systems.
This heat manifests itself in several forms:
- Gaseous : steam, vapors, hot air expelled,
- Liquid : wastewater, circuit flushing,
- Diffuse : losses due to radiation or insulation defects.
These are all untapped energy sources that can now be captured using proven technologies (heat exchangers, high-temperature heat pumps, etc.) and reinjected into useful applications such as district heating or domestic hot water.
Why are local authorities involved?
Local authorities play a strategic role in local energy planning (PCAET, PLUi, SRADDET, etc.). They have direct leverage to:
- to create or expand urban heating networks,
- to develop local energy resources,
- reduce dependence on fossil fuels and CO₂ emissions.
Local authorities: why recover waste heat?
Some key figures
- 52% of the waste heat comes from municipal waste incineration plants ,
- 43% of data centers,
- 5% of wastewater treatment plants.
In total, the recoverable heat is estimated at 8.4 TWh , of which 2.4 TWh is lost at temperatures above 100°C , ideal for direct thermal use.
Social equity
Energy recovered from waste heat makes it possible to provide cheap and stable heating over time, particularly for social housing. It strengthens solidarity between neighborhoods, reduces energy poverty , and promotes fair pricing on public heating networks.
Local jobs
The development of recovery projects creates a local circular economy generating jobsthat cannot be outsourced : energy engineering, maintenance, operation, network management… So many opportunities to strengthen the industrial and ecological dynamics of the territories.
Savings on bills
For local authorities, waste heat represents a lever for value creation :
- reduction of energy bills for public buildings,
- additional revenue for operators,
- access to low-cost heat for network users.
Local and sustainable energy
Waste heat is a local energy source, consumed on-site or near its production location. It is a free, renewable resource, not subject to fluctuations in global markets.
Decarbonization
During operation, the recovered waste heat emits 0 g of CO₂ per kWh of thermal energy. It thus contributes directly to the decarbonization of territories and to achieving the carbon neutrality set by the National Low Carbon Strategy (SNBC).
What are the possible valuations?
Direct heat
The recovered heat can:
- to meet the internal heating needs of a company,
- or be injected into an urban heating network to heat homes, schools, swimming pools or hospitals.
Conversion to electricity
Some sites choose to convert waste heat into electricity for internal use or injection into the grid. This approach relies on adapted thermodynamic cycles (ORC, Rankine, etc.).
How is waste heat recovered?
Before it can be utilized, waste heat must first be identified, captured, and transformed to meet the energy needs of buildings or networks. Its recovery relies on a methodical approach, combining diagnostics, thermal engineering, and technological solutions adapted to the local context.
- Identification of the heat source : via an energy diagnosis or a territorial mapping of thermal emissions.
- Recovery : installation of a heat exchanger at the outlet of the industrial process, a wastewater treatment plant or a data center.
- Valuation :
- injection into a heating network,
- domestic hot water production ,
- heating of public facilities.
- Optimization : use of high temperature heat pumps (HT heat pumps) to adapt the recovered heat to the needs of the network.
Regulatory framework and aid
Waste heat recovery is fully in line with the French and European regulatory framework for the energy transition. These regulations aim to encourage the use of local resources , reduce dependence on fossil fuels , and accelerate the decarbonization of regions.
A dynamic driven by the energy transition law
Adopted in 2015, the Energy Transition for Green Growth Act (LTECV) marked a turning point in French energy policy. It sets ambitious objectives: to halve final energy consumption by 2050 and to increase the share of renewable and recovered energy to 32% of the national energy mix. In this context, the recovery of waste heat emerges as a priority. The LTECV encourages local authorities and businesses to identify, capture, and reuse these untapped thermal resources, particularly through urban heating networks or territorial energy performance projects.
Good to know: local authorities are also subject to the tertiary sector decree! More information in our dedicated article.
The key role of the Heat Fund
Established by ADEME (the French Agency for Ecological Transition),the Heat Fund is one of the main financial support mechanisms for renewable or recovered heat production. It supports both feasibility studies and the work involved in recovering and injecting into a network. Local authorities can thus obtain subsidies covering a significant portion of the investment, making energy recovery projects economically viable, even in areas with moderate energy density. Beyond financial assistance, the Heat Fund also supports the structuring of local sectors, fostering the emergence of sustainable projects rooted in the real needs of local communities.
Good to know: Energy Savings Certificates ( CEE) help reduce investment costs related to the installation of recovery equipment by rewarding operations that generate energy savings.
A strong European impetus
At the European Union level, the Energy Efficiency Directive (EED) has, for several years, mandated a proactive approach to energy management. In particular, it requires large companies to conduct regular energy audits that include an assessment of their potential for recovering waste heat . This requirement aims to encourage the implementation of concrete energy recovery solutions, whether to reduce primary energy consumption or to supply local heating and cooling networks
By combining these three pillars (a clear national legislative framework, an incentive-based financial mechanism and a structuring European impetus), France is creating an environment conducive to the massive deployment of waste heat recovery.
Local authorities thus have concrete levers to act, by including their projects in a coherent approach to territorial energy transition.
Go further with Powesco
Beyond waste heat recovery, local authorities are now facing a range of regulatory obligations aimed at improving energy efficiency and decarbonizing public buildings and infrastructure. Powesco supports public and private stakeholders in meeting these requirementsby integrating solutions tailored to the specific needs of each region.
Photovoltaic panels
The APER law now mandates that all outdoor parking areas larger than 1,500 m² must be equipped withphotovoltaic canopies covering at least half of their surface area. These installations allow for local electricity production while providing protection for parked vehicles. Powesco assists local authorities in the design, sizing, and installation of these photovoltaic canopies, ensuring that electricity production is optimized for self-consumption or grid injection, in line with a commitment toenergy independence and ecological transition.
Charging stations for electric vehicles
With the LOM law, local authorities must now provide for the installation of electric vehicle charging stations or the pre-equipping of public and private car parks. This obligation particularly concerns large car parks, often associated with public buildings or commercial areas.
Powesco supports local authorities in deploying these infrastructures cost-effectively and efficiently, integrating financing through a deferred payment Energy Performance Contract or a performance-based contract such as an ESCO. This approach allows local authorities to implement these projects without using their initial budget.
FAQ
What forms of heat can be recovered in the service or industrial sector?
Waste heat can be available in several forms: low temperature (hot air, hot water), medium or high temperature (steam, smoke, combustion gases). Each form requires a specific technology for its efficient recovery and redistribution.
Can waste heat be used to produce electricity?
Yes, thanks to technologies like the Organic Rankine Cycle (ORC), waste heat can be converted into electricity. This can power servers, platforms, or local networks, contributing to theenergy self-sufficiency .
What technical means can be used to optimize heat recovery?
Solutions include heat exchangers, cogeneration, industrial boilers incorporating ORC cycles, and solar thermal technologies. Technical and regulatory support helps in choosing the most suitable solution for the industrial or commercial process.
Sources:
https://librairie.ademe.fr/index.php?controller=attachment&id_attachment=2540&preview=1
https://librairie.ademe.fr/index.php?controller=attachment&id_attachment=1731&preview=1
