SDE++: Renewable heat
Do you want to apply for biomass fermentation and combustion, composting, geothermal energy or solar thermal energy? On this page you will find the general conditions for the production of renewable heat and the technology-specific application conditions.
Biomass fermentation
You can apply for a subsidy for renewable heat in these 3 categories:
In the subcategory ‘All-purpose fermentation’, you can apply for a subsidy for almost all types of biomass. This also includes co-digestion of manure to produce heat, electricity, and combined heat and power (CHP). One condition is that the incoming biomass must produce at least 25 Nm³ of biogas (natural gas equivalent) per ton. For electricity and heat (CHP), you calculate the rated power output by adding the electric and heat capacity together.
Mono manure fermentation is used for the production of combined heat and power (CHP). The input must consist exclusively of livestock manure, with no co-products. There are three output categories for manure mono-fermentation:
- ≤110 kW
- >110 kW and ≤ 275 kW
- > 275 kW and ≤ 1,500 kW
- > 1,500 kW
For combined heat and power (CHP), the rated power output is determined by adding together the electrical and thermal outputs.
The ‘Continuation All-purpose fermentation’ and ‘Continuation Manure mono-fermentation’ categories are for SDE projects nearing the end of the subsidy period. The involved operating expenses and renovation expenses mean that these projects will usually have an unprofitable component.
This provides you with more certainty about the future of your power generation facility.
Combined applications
You can combine applications in the categories 'Mono manure digestion' and 'All-purpose fermentation'. This can be useful if you want to do the project together with other applicants, but only if all applications in the bundle get a subsidy.
If, on one day, the total amount of requested subsidy is higher than the available budget, we rank the applications by subsidy intensity in euros per ton of CO₂ reduction. For a bundled application, we use the highest amount from the applications in the bundle. If it is necessary to draw lots, we treat the bundle as one single application.
Supplying electricity to the grid at a negative price
Do you have an installation that produces electricity from a fermentation installation with a CHP? And do you supply electricity to the grid when the electricity price on the EPEX is negative? Then you will not receive SDE subsidy for that.
Probably on October 1 2025 we will change from hourly prices to 15-minute prices. From that moment, you will no longer get a subsidy for every 15-minute period when the price on the EPEX is negative.
Sewage treatment plant, improved sludge fermentation
You can apply for a subsidy for improved sludge digestion to produce renewable heat or electricity in a wastewater treatment plant (STP). It is not limited to one specific technology. This gives more options to use new and innovative techniques. STPs also differ a lot in size and type of installation. In your application, you must show that you can increase the current biogas production by at least 25%. The parts of the installation that make this extra biogas possible must be new.
Biomass combustion
For biomass combustion, you can get a subsidy for renewable heat and renewable electricity. There are 7 categories for biomass combustion:
- Boiler using liquid biomass with a capacity of 0.5 MWth or more and up to 100 MWe, for use in district heating.
- Boiler using liquid biomass with a capacity of 0.5 MWth or more and up to 100 MWe, for other uses.
- Large boiler using solid or liquid biomass with a thermal capacity of 5 MWth or more.
- Continuation for boilers using solid or liquid biomass with a minimum capacity of 5 MWth or more that have already received SDE subsidy before.
- Steam boiler using sustainable wood pellets with a minimum capacity of 5 MWth and less than 50 MWth.
- Steam boiler using sustainable wood pellets with a minimum capacity of 50 MWth or more.
- Burner using sustainable wood pellets for industrial use, with a capacity of 5 MWth or more (existing parts may be used for this category). The maximum limit is 100 MWe.
Wood biomass for high-grade heat only
Since 2021, there is no subsidy anymore for burning wood biomass (like thinnings and wood chips) to produce low-grade heat.
Do you burn woody biomass to produce high-value heat above 100 °C for an industrial use? Then you can still apply for a subsidy. Use in horticulture is not allowed. The 100 °C rule applies to the heat at the first user.
Subsidy only for heat
For the combustion categories, you only get a subsidy for the heat you produce. You are not allowed to use the heat to produce electricity.
Liquid biomass boilers ≥ 0.5 MWth
The category 'Boiler using liquid biomas' has different uses for the heat that is produced. These uses can have different possible benefits from the ETS (Emissions Trading System). That is why this category is split into 'district heating' and 'other use'.
Each year, you must show the sustainability of the liquid biomass with a report.
Continuation (formerly ‘lifetime extension’)
The continuation category is for SDE projects where the subsidy period is almost finished. Because of operating costs, these projects usually still have a financial gap. That is why a continuation category is available for these installations. It is meant for installations with a capacity of 5 MWth or more.
Also, using woody biomass is only allowed to produce high-value heat above 100 °C for industrial use. Use in horticulture is not allowed. The 100 °C requirement applies at the user side.
Fuel requirements
B-wood is not allowed in the combustion categories. When we calculate the base amount for these installations, we also take into account the higher price you pay for clean wood.
If you apply in a category made especially for sustainable wood pellets as fuel, you may use a maximum of 15% energy from A-wood pellets and a maximum of 25% from residues from refining A-wood pellets. In the SDE++, biorefining means a process where the main product replaces a fossil raw material. For example, lignin from the paper industry does not qualify. But lignin from making sugars from wood does qualify. If bioplastics are made from these sugars, this is a residue from biorefining.
If you use one of these techniques:
- boiler on solid or liquid biomass;
- steam boiler on wood pellets;
- continuation for boiler on solid or liquid biomass,
then at least 97% of the energy value of the fuel must be biogenic. This rule excludes burning waste, selected waste streams, or mixing with natural gas.
In all biomass combustion installations, you may also use liquid biomass. You must show the sustainability of this fuel.
Biomass sustainability requirements
If you use solid, liquid, or gaseous biomass and have a certain capacity, you must meet the sustainability requirements from the RED. The RED requirements depend on the input capacity of the production installation (see table below).
You have to prove that the biomass you use meets the RED requirements. You do this by using certification schemes approved by the European Commission (EC). Usually, your company also needs to be certified.
Read more about the requirements and limits on RED sustainability criteria for biomass for the SDE++ scheme.
| SDE++ categories, other than wood pellet installations | Applied power concept | RED criteria apply for a capacity of |
|---|---|---|
| Solid biomass for the production of heat and/or electricity | Nominal input power of the boiler | Less than or equal to 7.5 MW |
| Liquid biomass for the production of heat and/or electricity | Nominal input power of the boiler | No lower limit |
| Biogas production for the generation of heat and/or electricity | Nominal input power of the boiler/CHP | Less than or equal to 2 MW |
| Biogas production for injection into the gas grid | Nominal sustainable gas capacity | Less than or equal to 2 MW |
Composting
The composting process produces a large amount of low-grade heat. This heat can be used to warm buildings or greenhouses. Within this category of biomass, as described in the biomass classification for energy use (NTA 8003: 2017), composting is allowed.
One exception is manure (numbers 300 to 329 in NTA 8003: 2017). The use of manure is not allowed in this category.
There are no sustainability requirements set for composting.
Solar thermal energy
The category ‘Solar Thermal’ includes installations that use only ‘covered' collector or ‘solar-tracking concentrating’ collectors. These installations have a total thermal capacity of ≥ 140 kW. In your subsidy application, you fill in the aperture area or the surface area of the mirrors or lenses that concentrate sunlight.
There are 2 output classes for solar thermal. Because larger systems are more cost-effective, a lower base amount is set for this category. The base energy price and correction amount are also different for small and large installations.
Lower limit
The lower limit for solar thermal energy in the SDE++ scheme is 140 kWth. Smaller systems may be eligible for the Investeringssubsidie duurzame energie en energiebesparing (ISDE) (Sustainable Energy Investment Grant).
The thermal output of the installation in kW is equal to the total aperture area of the covered collectors or the surface area of the mirrors or lenses that concentrate sunlight in square meters, multiplied by a factor of 0.7.
Light-transmitting layer
If you want to qualify for the subsidy, the light-absorbing surface must be integrated with the light-transmitting layer. The light-translucent layer provides insulation, like a glass plate or tube.
The glazing of a greenhouse is a light-translucent layer, and PVT also has a light-translucent layer, but neither forms an integrated whole with the light-absorbing surface. For this reason, they are not eligible for subsidy in the ‘Solar Thermal’ category.
Geothermal energy
Geothermal energy (or earth heat) qualifies for SDE++ subsidy. We make a distinction between geothermal for producing renewable heat and geothermal for producing low carbon heat.
Deep or shallow geothermal energy with a heat pump using a halogen-free refrigerant as part of the production installation falls under low-CO₂ heat.
Within renewable heat and low carbon heat, there are different categories:
- Geothermal energy system with a minimum depth of 1,500 metres and a power output of:
- ≤ 12 MWth
- > 12 MWth and ≤ 20 MWth
- > 20 MWth
- Geothermal energy system with a minimum depth of 1,500 metres, in which existing oil or gas wells are used for one or both wells in the doublet and with a power output of:
- ≤ 12 MWth
- > 12 MWth and ≤ 20 MWth
- > 20 MWth
- Geothermal energy system involving expansion of a power generation facility with at least one additional well with a minimum depth of 1,500 metres.
- Geothermal energy system with a minimum depth of 1,500 metres of which the heat is used in the built environment based on 5,000 full-load hours.
- Geothermal energy system with a minimum depth of 1,500 metres of which the heat is used in the built environment based on 3,500 full-load hours and with a power output of:
- ≤ 12 MWth
- > 12 MWth and ≤ 20 MWth
- > 20 MWth
- Geothermal energy system with a depth between 500 and 1,500 metres, of which the heat is upgraded using a heat pump based on 3,500 full-load hours.
- Geothermal energy system with a depth between 500 and 1,500 metres, of which the heat is upgraded using a heat pump, used in the built environment, and based on 6,000 full-load hours and with a power output of:
- ≤ 12 MWth
- > 12 MWth
- Geothermal energy at a depth of at least 1,500 meters, where the heat is upgraded with a heat pump. The heat pump has a nominal thermal power of 20% of the geothermal power of the production installation. All produced heat is used in a heat network or heating system with a supply temperature to users of at least 90 °C during the heating season.
This temperature is the required input liquid temperature for a heat network or heating system, based on the heating curve at an outside temperature of -10 °C or lower. The heat is used for heating buildings, with 6,000 full load hours.
The term 'user' means the first user of the heat.
The compression heat pump for these three categories has a nominal thermal power of at least 500 kWth and a COP value of at least 2.5. You may only use a heat pump with a halogen-free refrigerant.
Download a table with tariffs for your installation
Would you like to know the amounts that apply to the category you are interested in? Download the Table of Tariffs for Renewable Heat SDE++ 2025.
This download is in Dutch. We wil publish the translated version as soon as it is ready.
Download a table with documents you need
Would you like to know which attachments you need to include with your application? Download the Table Documents to Attach to Renewable Heat Subsidy Applications ('Tabel verplichte bijlagen SDE++ 2025', Hernieuwbare warmte).
This download is in Dutch. We wil publish the translated version as soon as it is ready.
Emission Trading System
The Emission Trading System (ETS) is the system in Europe for trading CO2 emissions from industry. A company must hand in one emission allowance for every ton (1,000 kilograms) of CO2 it emits. Companies can buy and sell these emission allowances. This way, industry must pay for the CO2 it produces.
The ETS is designed to make European industry reduce emissions step by step until it reaches zero in 2057.
Do you benefit from the ETS because of your installation? Then we adjust this ETS benefit in the correction amount of the SDE++. This situation can change during the production period. The SDE++ allows us to adjust this during that period.
If you produce renewable heat, you may benefit from the ETS if your production installation is part of an ETS installation. For each type of production installation, an ETS correction is set. When we review your subsidy application and your installation is not (or no longer) part of an ETS installation, then this part is not included in the correction amount.
Do you get a subsidy for biomass fermentation with combined production of renewable electricity and renewable heat? Then we only apply the ETS correction if the installation is part of an ETS installation.
- Ministry of Climate Policy and Green Growth
