Sustainable and green energy: how it really works
By Laurens Arends · updated 05-10-2026
What is sustainable energy?
Sustainable and renewable energy are often used as synonyms. The European Renewable Energy Directive, revised in 2023, counts solar, wind, hydropower, geothermal energy, ambient heat and biomass, among others, as renewable sources. Green electricity is only the electricity part. Sustainable energy also includes renewable heat and fuels.
Grey energy comes from fossil sources such as coal, oil and natural gas. Renewable does not automatically mean without environmental impact. Biomass, for example, is renewable, but there is certainly an ecological impact if forest is felled for it and not replenished. So assess an energy source on the entire life cycle, land use, impact on nature, raw materials, waste and security of supply.
How sustainable is the energy mix in the Netherlands and Europe?
According to the provisional CBS figures from June 2026, 22,7% of Dutch gross final energy consumption came from renewable sources in 2025. That is something very different from the share of green electricity. According to the CBS in March 2026, renewable sources supplied 49% of Dutch electricity production in 2025. Heat, transport and industry are becoming sustainable more slowly than electricity.
| Figure for 2025 | Netherlands | European Union |
|---|---|---|
| Renewable in total gross final energy consumption | 22,7% | 26,2% |
| Share of renewable electricity | 49,0% of production | 49,9% of gross electricity consumption |
Sources: provisional figures from CBS (2026) and Eurostat (July 2026). The Dutch and European electricity percentages do not use the same denominator and are therefore not exactly comparable.
The binding EU target for 2030 is 42,5%. According to Eurostat (2026), the share must rise by an average of 3,3 percentage points per year from 2026 to achieve this. According to CBS (2026), the Netherlands has agreed a national contribution of 39%.
Sources of sustainable energy
The Netherlands used 401 PJ of renewable energy in 2025. Of this, 34% came from biomass, around 30% from wind, 23% from sun and 9% from ambient heat via heat pumps. Abroad, other sources of sustainable energy are often used as well, including hydropower.
Wind energy
According to CBS, wind energy supplied 121 PJ in 2025. Wind energy is sustainable energy. It has limited CO2 emissions, a consequence of, among other things, the production of the large wind turbines. An international life cycle analysis by UNECE from 2021 arrives at 7,8 to 16 grams of CO₂ equivalent per kWh for onshore wind and 12 to 23 grams for offshore wind. When choosing a location, account must also be taken of nature, noise, local residents and the possible grid connection.
Solar energy
According to CBS (2026), solar energy supplied 93 PJ in 2025. That is 19% more than in 2024. This can mainly be explained by a sunny year and 5% more capacity. In 2021, UNECE cited 8 to 83 grams of CO₂ equivalent per kWh over the life cycle for solar panels. Production technology, lifespan, solar irradiation and the electricity mix during manufacture explain part of that rather wide range.
Biomass
At 34% in 2025, biomass was the largest category within Dutch renewable energy use. According to CBS (2026), this was partly due to more biofuels in transport. Biomass is not automatically climate-neutral: the outcome depends on the raw material, land use, transport and regrowth time. In 2024, PBL concluded that wood from well-managed forests is not automatically emission-free or low-emission, but is also not by definition worse than fossil fuels.
Hydropower
Hydropower is important in mountainous European countries, but hardly at all in the flat Netherlands. In March 2026, CBS reported only 57 million kWh of hydropower for 2025, less than 0,1% of all Dutch renewable electricity production. Hydropower can be dispatchable, but dams can also disrupt river ecosystems. In 2021, UNECE accordingly found a wide international climate range of 6 to 147 grams of CO₂ equivalent per kWh.
Geothermal energy, ground heat and ambient heat
Geothermal energy is also used in the Netherlands. According to RVO (2020), this has been done since 2007 with wells deeper than 500 metres, mainly for greenhouses and heat networks. In homes, it usually concerns ambient heat from the outside air, ventilation air, the ground or groundwater. A heat pump extracts this heat from the environment at a low temperature and, with an electrically driven compressor, brings it to a temperature that is usable for heating and hot water.
A heat pump does not create energy out of nothing. According to Milieu Centraal (2026), a heat pump typically supplies 3 to 5 kWh of heat with 1 kWh of electricity. With a COP of 4, that output consists, for example, of 1 kWh of supplied electricity and 3 kWh of heat from the environment. In everyday language, this is sometimes called an efficiency of 400%. Technically, we speak of a coefficient of performance or COP.
CBS counted about 34 PJ of renewable heat from outside air and ground via heat pumps in 2025. This national figure covers not only homes, but also non-residential buildings and other applications. Moreover, it is partly a model calculation. In the CBS study on 2024, the uncertainty is estimated at about 40% for outside air heat and around 25% for ground energy.
Tidal energy, wave energy and blue energy
Tidal energy uses the difference in height or the current created by ebb and flood. Tidal currents can be predicted years in advance, but do not constantly deliver the same power. Around the turn of the tide, when ebb changes to flood or vice versa, production drops sharply. The potential is predictable, but suitable locations are scarce.
Construction and maintenance in salt water are expensive and a dam can change currents, sediment and ecosystems. According to the EU Blue Economy Report 2025, tidal energy with a basin is technically proven, but further application is mainly limited by site selection and local environmental effects. The French tidal power station La Rance has a capacity of 240 MW, but since 2011 no new large tidal basin power station has been built anywhere in the world.
Newer forms of energy from the sea are still small. The Netherlands is, however, gaining practical experience. In 2015, five tidal turbines were installed in the Oosterscheldekering. Deltares studied, among other things, the consequences for currents, the storm surge barrier and marine mammals. In addition, wave energy and blue energy are being researched. Wave energy converts the movement of waves into electricity. Blue or osmotic energy uses membranes to exploit the difference in salinity between river water and seawater.
Batteries make sustainable energy more usable
A battery is not a sustainable energy source. It does not produce new energy, but shifts electricity to a different moment. A battery can, for example, charge during a sunny afternoon and feed the electricity back in the evening. That is useful when, during a dark and windless evening peak, extra gas-fired power stations would otherwise be needed.
A scientific comparison by Beuse and others in Joule (2021) examined four applications of energy storage in electricity systems resembling seven European countries. The researchers found large differences between countries and applications.
Due to conversion losses and changes in the dispatch of power plants, storage can lower emissions, but under unfavourable circumstances it can also increase them. For the climate, a battery should therefore charge when marginal emissions are low and discharge when this avoids fossil generation. So steering only on the electricity price is not always enough.
Batteries are mainly suitable for short shifts. According to the International Energy Agency (IEA, 2024), batteries typically provide one to eight hours of flexibility. They respond within a few seconds and are therefore suitable for supporting the balance and frequency of the electricity grid. They can store solar electricity, absorb demand peaks and prevent wind or solar farms from being switched off during a temporary surplus.
The number of large battery parks is growing rapidly
The most recent comparable CBS figures (provisional figures for 2023 and 2024, updated in 2026) concern battery systems with more than 1 MWh of storage capacity. Home batteries are therefore not included here.
| Year | Battery systems | Power | Storage capacity |
|---|---|---|---|
| 2023 | 40 | 229 MW | 343 MWh |
| 2024 | 84 | 350 MW | 620 MWh |
The number of registered large battery systems thus increased by 110% in one year. Power rose by 53% and storage capacity by 81%. The figures show rapid growth, but 620 MWh remains limited compared with total Dutch electricity consumption. With a combined discharge power of 350 MW, the full capacity would theoretically last less than two hours.
In Europe too, growth is shifting to battery parks. According to the trade association SolarPower Europe (2026), 36 GWh of battery capacity was added in Europe in 2025, 48% more than a year earlier. For the first time, more than half of the new capacity came from large-scale installations. These figures are not limited to the EU; they also include the United Kingdom, Switzerland, Ukraine and Turkey.
The Coo power station works like a large water battery
Electricity can also be stored without a chemical battery. The Belgian power station at Coo is a good example of this. Here, water is pumped to higher reservoirs when a lot of electricity is available. During a demand peak, the water flows back down and drives turbines. This is called pumped storage or pumped hydro storage.
According to operator ENGIE, Coo can deliver a maximum of 1.089 MW for almost six hours. According to our calculation, that amounts to about 6,5 GWh of storage, more than ten times the combined capacity of the large Dutch battery systems that CBS registered for 2024. Coo can also start producing within two minutes and is therefore suitable for absorbing sudden shortages on the Belgian electricity grid.
How to check whether green electricity is really green
Green and grey electricity run through the same grid. So you cannot determine which electrons come out of your socket. Your contract determines which production is administratively set against your consumption. This is done with Guarantees of Origin. One GO represents 1 MWh, or 1.000 kWh, of sustainably generated energy.
The certificate states the source, installation, production date and location and is valid until one year after the month of production. For green electricity sold, the supplier cancels an equal number of matching GOs, so that the same proof is not used twice.
Check the electricity label of your product and that of the total supply mix. A supplier must publish the labels for the previous year by 1 May each year at the latest. On our brand pages, you can see for yourself how energy suppliers purchase their electricity and what origin they promise. You can take this information into account when choosing a new energy supplier.
Misconceptions about green energy
Only the green electricity you have chosen comes out of your socket
Not physically. On the grid, all sources mix. You are buying the certainty that an equal amount of renewable production has been accounted for with GOs for your consumption. The electricity is technically the same; the claim of origin is entirely administrative.
Foreign GOs are fraud
No. Under European rules, foreign GOs are valid proof that renewable energy has been generated elsewhere in Europe. They are sometimes called ‘sjoemelstroom’, but that mainly has to do with any perverse incentives they create. The reason for this is that a cheap GO from an existing foreign hydropower station can provide little extra incentive for new Dutch generation.
HIER's Groene Stroom Checker (2026) estimates that about 34% of Dutch green electricity products have been made green with foreign certificates. HIER only calls electricity from Dutch renewable sources ‘truly green’. That is a stricter choice of origin than is legally required. If you want to make a local effect more likely, also look at the country of generation and the supplier's investments.
Renewable energy has no emissions or environmental damage
This is not true. Construction, extraction of materials, transport and disposal also count. The UNECE life cycle analysis from 2021 does show that wind and solar come out much lower than gas-fired power stations at 403 to 513 grams and coal-fired power stations at 751 to 1.095 grams of CO₂ equivalent per kWh.
These global ranges show an order of magnitude, not the precise footprint of a single Dutch project. Even with renewable energy there is still always some form of damage that has to be compensated in some way, for example through afforestation projects. The damage is, however, much smaller than with gas or coal-fired power stations.
Nuclear energy is renewable energy
Nuclear energy is low in CO₂, but not renewable. The European regulation from 2022 explicitly calls nuclear energy a low-carbon, non-renewable source. The available source material is limited and there is the problem of nuclear waste. Under strict conditions, certain projects do fall within the European taxonomy for sustainable investments.
Hydrogen is automatically green energy
Hydrogen is an energy carrier, not a primary energy source. This means that hydrogen works more like a battery: it takes a lot of energy to make hydrogen. That hydrogen can then be converted back into electricity at another moment.
The big advantage is that this can happen much later: whereas a battery park stores electricity for only a few hours, hydrogen can be used for seasonal storage. Do take care, though, because hydrogen in itself is not yet green. Hydrogen is only green if it is made with demonstrably renewable electricity. According to the IEA Global Hydrogen Review 2026, less than 1% of global production in 2025 was low-emission.
Choosing sustainable and green energy yourself
Start with your contract. Check whether the GOs are Dutch or foreign and which source they come from. Also consult the recent electricity label. Then assess the supplier itself: a green product does not automatically mean that the whole company invests sustainably. Find out, for example, which sustainable investments it makes in the Netherlands and which other companies it works with.
In addition, it is a good idea to reduce your own consumption. With our saving tips less energy needs to be generated and transported. A tip: choose an affordable energy contract and go all out for green energy deals. What you save, you can use to make your own home more sustainable.
Frequently asked questions about sustainable energy
What is the difference between sustainable energy and green electricity?
Sustainable energy is the broad category and includes renewable electricity, heat and fuels. Green electricity is only the electricity part that is linked to renewable production with matching GOs.
Is green electricity from abroad really green?
Yes, according to the statutory European administration, the GO proves that an equal amount of renewable energy has been generated somewhere in Europe. The physical electricity does not necessarily come from that country to your home and a certificate from existing production does not automatically stimulate new generation in the Netherlands.
Is green gas the same as CO₂-offset gas?
No. Green gas is made from renewable sources, for example biogas from digestion or sewage treatment. CO₂-offset gas remains fossil natural gas. The provider does try to offset the emissions elsewhere, for example through afforestation projects.
Is a heat network always sustainable?
No. Sustainability depends on the heat source, the temperature, pipe losses and the fuel for supplementary firing during cold peaks. RVO (2026) writes that existing heat networks still mainly use heat from power stations and waste incinerators, while geothermal energy and other sustainable sources are gradually becoming more important. A heat network can, however, switch to cleaner sources during its lifetime.
How do you make a home gas-free?
A gas-free home uses no natural gas for heating, hot water or cooking. First limit the heat demand with insulation and suitable ventilation. Then you can choose, for example, a fully electric heat pump and electric cooking. A hybrid heat pump reduces gas consumption, but does not make your home gas-free because the central heating boiler still helps out and usually heats the tap water.
Is a solar water heater enough to get off natural gas?
A solar water heater uses solar heat for hot tap water and is therefore a form of local sustainable energy. According to Vereniging Eigen Huis and Milieu Centraal, a Dutch household can save about 40% to 50% on the gas for hot water with it. Especially in winter, additional heating remains necessary.
Is infrared heating sustainable?
An infrared panel can save energy if you use it to heat a single workspace, bathroom or seating area for a short time and keep the main heating lower. For the whole home, it is not an economical solution. In Milieu Centraal's Dutch corner house model, updated on 31 August 2026, infrared panels plus a heat pump water heater use about twice as much electricity as a fully electric heat pump.
Do you have to insulate before you get solar panels?
No. Solar panels produce electricity, while insulation limits your home's heat loss. Both measures can be carried out separately. If your roof needs to be renewed soon, do combine the installation of solar panels with roof insulation straight away. That way you avoid the panels having to come off the roof temporarily later on.