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New Future for small and medium size wind turbines in Belgium!

‘More wind turbines in a shorter period of time’, those were the main principles in the ‘Windpower 2020’ wind plan by Flemish Minister of Energy Bart Tommelein and his colleague Joke Schauvliege from the department ‘Environment (CD&V)’. Steps have already been taken to remove a number of obstacles for the construction of wind turbines. Minister Tommelein has introduced a ‘support-system’ to encourage the construction of small and medium sized wind turbines.

Small wind turbines are turbines with a hub-height of up to 15 meters. Medium sized wind turbines start with a hub-height of 15 meters up to a capacity of 300 kilowatts. For small business companies, farms and hospitals, small and medium sized wind turbines are an excellent way to produce their own renewable ‘green’ energy. Initiators receive investment support at the start of their project which can be as high as 70 percent of the investment.

The first call has delivered 14 new wind turbine projects. The call ran from December 3, 2018 to January 24, 2019 and worked with a comparative bidding procedure. Projects that did not make it were either too expensive or did not meet the conditions. The selected projects will only receive investment support so afterwards there will no longer be any production aid in the form of green certificates during the operational period of the wind turbine.

Flemish Minister for Energy Lydia Peeters: “The Flemish energy policy focuses on renewable sources. As wind energy can also be generated at a lower altitude, we worked out a specific call for small and medium-sized wind turbines. The selected projects can therefore count on investment support to realize their project. ”

26 projects were received in two months; 18 of these projects were declared admissible and 14 were finally selected. It concerns agricultural and waste processing companies and even includes a single brewery. The majority of applicants, no fewer than 12, come from West Flanders. 2 projects will be realized in the province of Antwerp. The projects were assessed and ranked according to the intended return in proportion to the aid applied for. Projects that were too expensive were therefore not eligible.

So far, this new call has been an unlikely big success. It shows that more and more organizations and small and medium sized companies are seeing the possibilities that a small or medium-sized wind turbine offers them. Thanks to investment support, many new wind turbines can be built and the Flemish government avoids over subsidization.

The second call of 2019 ran from March 28 until May 30 2019 and there are serious plans for a third call in 2019 as well. Flemish companies that are interested in a mid-sized wind turbine between 10 and 300 kilowatts can have a look at our website www.windenergysolutions.nl or contact our Project Manager Sjoerd Overpelt for more information, advice and support for a possible wind project.

Sjoerd Overpelt
Tel: +31 6 8352 3856

2 blade 3 blade

How many blades are best for wind energy production?

The vast majority of wind turbines currently being installed have three blades. Why not four? Or two? Or a lot more to catch as much wind as possible?

The quick answer is that a two bladed wind turbine is already great for great efficiency. With two blades you need significantly less material, construction and maintenance costs. A third or fourth rotor blade makes the wind turbine marginally more efficient, while the construction and material costs increase considerably. The four blades of our historic wind mills were more of a practical choice.


The four blades of our historic wind mills were more of a practical choice.

Betz Law

Albert Betz formulated the law in 1919 that an ideal rotor can extract a maximum of 59% of the energy from the wind. If you get more energy out of the wind, the wind slows down further, that reduces the supply of wind to the turbine. An ideal rotor has endlessly infinitely narrow turbine blades, but according to a document that Siemens drew up in 2007 in which they deal with our question, it is stated that modern three-bladed wind turbines come to 80% of the Betz limit thanks to a smart blade design and a well-chosen rotation speed; a two-bladed turbine would achieve 5% less efficiency, but will have a higher return on investment because of the lower costs.

Two-bladed wind turbines offer a number of distinct advantages over three-bladed wind turbines.

The major advantage of having a reduced number of blades (and pitch drives) is the rotor weight (and therefore material) they approximately 30% less heavy than a comparable three-bladed rotor (Aerodyn engineering GmbH, 2014). Moreover, as two-bladed rotors operate at a higher rotational speed, the torque on the shaft is lower and more consequently the rotor and nacelle (which houses for instance the generator and drivetrain) are lighter. Another conveinience of a rotor with less than three blades is that they can be turned horizontally durig storm so they are less likely to be hit by lightning.

Two-bladed rotors are approximately 30% less heavy than a comparable three-bladed rotor

Another advantage can be found during transportation and construction: a two-bladed rotor can be transported fully preassembled and pretested on a ship’s deck to the wind farm site (De Vries, 2011). Finally, extreme loads can be considerably reduced by using horizontal parking of the rotor (Aerodyn engineering GmbH, 2014). Due to reduced extreme loads, the tower and foundation can be designed lighter.

Matter of taste

Roberto Delgado, principal engineer at 2-B Energy, it’s a matter of taste to choose between two or three bladed wind turbines. Some just prefer three-bladed models because they find them more aesthetic. Delgado wants to breathe new life into the two-bladed wind turbines. A two-bladed 6 MW 2-B Energy wind turbine has now been installed in Eemshaven for six years. Through individual pitch control (IPC), independently controlling the pitch of each turbine blade, this wind turbine can take away much of the dynamic load. Check out how our piching technique works https://windenergysolutions.nl/technology/

Storm resilience

A major disadvantage in areas with the most constant good wind is that they can turn into strong storms and hurricanes periodically. Most wind turbines cannot withstand the high wind speeds that these weather conditions entail. 2-bladed wind turbines can easily be brought down quickly with one crane intead of two cranes most thee-bladed turbines demand.

Our in-board-hoisting-crane can greatly reduce the maintenance costs of the two-bladed wind energy installations.

Our entire range of wind turbines can be equipped with an in-board-hoisting-crane which can be easily operated to secure the entire technical installation of the turbine without external crane within a few hours. In this way, no high costs have to be incurred for supplying and using any mobile crane installation.

A second advantage of this built-in elevator construction is that inspections on the rotor and major maintenance can also be carried out without equipment from external sources. In addition to the advantages of the installation compared to three-bladed wind turbines, this greatly reduces the maintenance costs of the two-bladed wind energy installations.

Check out our animation of the in-board-hoisting-crane in action.


Delgado foresees turbines of 10, 12 or more megawatts are going back to the two-bladed design. Dynamic load can always be better controlled with good steering. According to Delgado, a two-blade design for a wind turbine in the year 2019 has less than 3% lower efficiency than its three-leaf counterpart with the same diameter. You then get extra electricity from longer turbine blades, while you can still continue to benefit from lower construction, material and maintenance costs.

A number of companies have begun developing and building large two-bladed wind turbines (Schorbach and Dalhoff, 2012; Clover and Snieckus, 2014). This renewed interest in two-bladed wind turbines is mainly motivated by the increased focus on offshore wind energy. Cost of energy reduction of 10−12% is stated and in Clover and Snieckus (2014) a 20% reduction, on paper, is mentioned for two-bladed wind turbines. The potential cost of energy reduction makes that two-bladed turbines are an interesting opportunity which manufactures are actively exploring.


The sustainable and profitable path forward for owners of aging wind turbines

The wind energy sector is set for a development boom for the coming years. Nations around the world are gearing up for a substantial expansion in renewable energy to offset concerns over energy security and to meet strict environmental targets and timetables.

When it comes to wind power most of the focus is being put on offshore projects and the promise of larger than ever wind farms and turbines far out to sea. But operators and developers should not be so quick to downplay the potential of the onshore wind sector.

Too old some say, citing farms dating back to the 1980s. Not enough popular support to develop on new greenfield sites say others, and anyway all of the ‘windiest’ sites have already been taken haven’t they?
All true, and indeed given that a typical wind turbine has a product lifetime 20 years there are therefore increasing questions over the reliability and productivity of hundreds of existing onshore wind farms worldwide as developers and operators strive to meet ever more stringent quotas and demand.


All of the ‘windiest’ sites have already been taken haven’t they?


Onshore wind farms

Onshore wind farms can substantially contribute to the great new era of wind without the need for new site locations.

The options are retrofitting, essentially improving an existing turbines efficiency and capacity by fitting new technology such as better grid connections or the latest blade designs, and repowering, decommissioning an existing turbine and building a more modern and powerful version. The UK, Germany, Denmark, the Netherlands and the US are undertaking the majority of repowering and retrofitting projects at present. This is perhaps unsurprising given their ‘pioneering’ status in the wind industry and hence a greater number of aged wind farms than elsewhere.
Emerging wind markets such as China and India though hold significant long-term potential with India already seeing some repowering activity.

The likelihood of failure simply increases in older turbines.


Repowering vs retrofitting

The likelihood of failure simply increases in older turbines and therefore the repair costs rise in proportion. This enormously enhances the potential profitability of repowering or retrofitting the old technology. The only real question is which of both options to take? The first, i.e. replacing old wind turbines with new ones, has its drawbacks because acquisition prices are high and the replacement involves a number of administrative steps that can get to last longer, besides having to add the time of acquisition and installation of the wind turbine itself.

Replacing part or all of the turbines before the end of their lifetime with new more efficient and more powerful machines

Repowering can refer to a single wind turbine or to a whole wind farm replacing part or all of the turbines before the end of their lifetime with new more efficient and more powerful machines. It can also be used to rearrange the location of the turbines in order to better integrate them into the local planning of residential areas. It is seen as a better option than building a new site at a different less windy location as most of the ‘windiest’ sites have already been developed on.

The ability to re-use part of the infrastructures already developed on site such as roads and grid connection also means less capital investment than building from scratch. Planning permission should also be easier from an existing site.

Overall an operator’s O&M costs are reduced after repowering projects thanks to newer and more efficient technology and economies of scale.
Prohibitive factors against repowering included temporary loss of revenue until the completion of a project, deemed only particularly beneficial for small-size turbines, more expensive and too complex.



The second solution that owners or operators can choose is the overhaul of the turbine, which means to renew some electrical and mechanical components of existing turbines and update the wind turbine control system.

Fitting in new technology such as better grid connections or the latest blade designs.

The main benefits of retrofitting include reduction of future running costs due to the better reliability of the replaced parts and increased productivity. Indeed it is estimated that retrofitting can improve reliability and productivity by up to 30%.

The cost of a retrofitting option varies but in general, components that are suitable for retrofitting don’t cost more than the O&M specified components and take no longer to install. It also has little effect on a turbine’s insurance or certification.


How are turbines retrofitted?

The retrofitting process consists in integrating a frequency converter equipped with the latest technology in power electronics and the renewal of some mechanical and electrical components.

The integration of the converter allows the wind turbine operate at variable speed to adapt its speed to the wind conditions as do the new wind turbines following current standards. This allows them to work at the optimum operating point for maximum energy transfer between the wind and the blades and smooth operation of the mechanical drive.

In addition, the cost of retrofitting is significantly less than the equivalent of a new wind turbine and its installation time is reduced depending on the owner’s needs and the conditions existing prior to retrofit.

The cost of retrofitting is significantly less than the equivalent of a new wind turbine.


Political support

Some industry players want to see better financial incentives given to operators such as more generous feed-in-tariffs to make repowering projects more economic. However that isn’t proving easy in today’s financial climate. I heard one leading developer say: “There is a strong belief that in the next few years there will be an easier planning regime, but that isn’t visible at the moment. So in all permitting is a problem.”

Whatever option is taken continued political support is vital. The ability of repowering and retrofitting to boost the wind sector’s capacity and productivity, not only in developed countries but also emerging markets, will be mute if governments are cutting renewable subsidies.


Wind Energy Solutions

At WES we have developed a solution to modernize aging wind turbines so that they can be profitable again. Although new wind turbines occupy their own position in the wind energy mix, there is also a growing demand to revitalize assets of a certain age.
With the maturity of the market for onshore wind power, assets are aging and many turbines have already completed their lifetime period.

Repowering and retrofitting offer a sustainable and profitable path forward and the opportunity should be grasped by all.

View all our turbines and options


Do you want to know what the best solution is for your business?

Agro PV

Land use efficiency dramatically increases through dual use

The joint project “Agrophotovoltaic – Efficient Land Use Resource” (APV-Resola) has been testing solar power production and agriculture, in an efficient way, on the same area for more than two years. Solar modules with an output of 194 kW were installed at a height of five meters above a 0.3-hectare field on Lake Constance (German: Bodensee). In the first project year 2017, the project consortium headed by the Fraunhofer Institute for Solar Energy Systems (ISE) has already demonstrated an increase in efficient land use to 160 percent. This result was again significantly exceeded in 2018.

As the Fraunhofer ISE reports, the partial shading among the solar modules increased agricultural yields in the hot summer of 2018, while the high solar radiation boosted solar power production. As a result, land use efficiency was 186 percent, as the researchers calculated.

Farmers record higher yields

Farmers of the Demeter farm community Heggelbach recorded higher yields of three of the four cultivated crops (winter wheat, potatoes, clover grass, celery) under the APV-Resola plant than on the reference area without solar modules. Celery benefited most (+12 percent), while winter wheat gained 3 percent and clover a minus 8 percent. “In terms of potatoes, the land use efficiency increased by 86 percent per hectare,” emphasizes project manager Stephan Schindele from Fraunhofer ISE.

We assume that the plants coped better with the drought-induced heat summer of 2018 due to the shading under the semitransparent solar modules.

Monitoring microclimatic conditions

In addition to stock development, yield and yield quality, scientists from the University of Hohenheim also collected data on the microclimatic conditions underneith and next to the APV-Resola plant. The photosynthetic solar radiation under the APV system was about 30 percent lower than on the reference surface. In addition to solar radiation, the PV modules primarily influenced precipitation distribution and soil temperature. The soil temperature under the panels was below that of the reference surface in spring and summer, while the air temperature was identical. In the hot and dry summer months of 2018, the soil moisture in the wheat stock under the PV panels was higher than on the reference area. In the winter months and other cultures, however, it was lower.

Better numbers despite extremely dry summer

“We assume that the plants better cope with the drought-induced heat summer of 2018 due to shading under the semitransparent solar modules,” says agronomist Andrea Ehmann. “This also illustrates the potential of the APV for dry regions, but also the need for further experiments in other climatic regions as well as with additional crop species”, adds her colleague Axel Weselek.

Agrophotovoltaic brings synergy effects for agriculture

double land usage

The solar irradiation in 2018, at 1,319.7 kWh per square meter, was 8.4 percent above the previous year. This increased the solar power production in the crop year 2018 by two percent to just under 250 MWh, which corresponded to an “exceptionally good” specific yield of 1,285.3 kWh per installed kilowatt peak. With electricity generation costs per kilowatt-hour, electricity from an agro-photovoltaic system is already competitive with small PV rooftop systems, and researchers are also counting on falling costs due to learning and scaling effects.

Agro-fotovoltaïsche installatie nu al concurrerend met kleine PV-opdaksystemen.

Increase in electricity demand

If the solar power is stored and used directly on site, as in the case of the Heggelbach farm community, additional sources of income are created for farmers through synergy effects. The use of electric vehicles is also gaining

“If policy permits, agro-photovoltaic can be the answer to the tank-or-plate discussion, because technically, farmers can do both by serving twice arable land in their core food production and by contributing to solar power to expand electromobility and protect the climate, “says Schindele.

Technology offers potential for dry land

In a project within the framework of the EU program Horizon 2020, the Fraunhofer researchers and their partners in Algeria are examining how the APV systems affect the water balance. In addition to reduced evaporation and lower temperatures, rainwater harvesting with PV modules also plays a role.

The project APV-Resola is funded by the Federal Ministry of Education and Research and FONA – Forschung für nachhaltige Entwicklung  (Research for Sustainable Development). It is a joint project of Fraunhofer ISE, BayWa r.e. Solar Projects GmbH, Elektrizitätswerke Schönau, Hofgemeinschaft Heggelbach, Karlsruhe Institute of Technology, Regional aliance Bodensee-Oberschwaben and the University of Hohenheim. (Post picture: BayWa r.e.)


Add a wind turbine to your energy generation

For the electricity needed during the winter months, a private wind turbine at an agricultural company is ideal. Wind turbines produce the most electricity in the winter, whereas solar panels do this in the summer. Together they make the ideal combination to provide an agricultural company with electricity all year round. Especially in regions with sufficient wind, generating wind energy is much cheaper than storing solar energy in batteries.

View all our turbines and options


Do you want to know what the best green energy solution is for your business?

Agro PV

Optimale efficiëntie, bij dubbele functie landbouwgrond

Het gezamenlijke project “Agro-fotovoltaïk – Efficiënte landbouwgrond” (APV-Resola) test zonne-energieproductie en landbouw op een efficiënte manier Deze test vindt momenteel al twee jaar plaats op hetzelfde stuk land, om de uitkomst op verschillende gewassen onder de zelfde omstandigheden goed te onderzoeken. Zonnepanelen met een vermogen van 194 kW zijn geïnstalleerd op een hoogte van vijf meter boven een veld van 0,3 hectare aan het Bodenmeer (Duits: Bodensee). In het eerste projectjaar (2017) heeft het projectconsortium onder leiding van het Fraunhofer Instituut voor zonne-energiesystemen (ISE) al een toename van efficiënt landgebruik tot 160 procent laten zien. Dit resultaat werd aanzienlijk overtroffen in 2018 met 183 procent ten opzichte van afzonderlijke toepassingen.

Boeren registreerden hogere opbrengsten

De Fraunhofer ISE meldt, verhoogde productie door de gedeeltelijke schaduw tussen de zonnemodules de landbouwopbrengsten zelfs in de hete zomer van 2018. De hoge zonnestraling kon door de panelen deels afgeschermd worden, terwijl deze straling de productie van zonne-energie extra ten goede kwam. Dientengevolge, was de efficiëntie van het landgebruik 186 procent, zoals de onderzoekers berekenden.

Boeren van de Demeter boerderijgemeenschap Heggelbach registreerden hogere opbrengsten van drie van de vier gecultiveerde gewassen (wintertarwe, aardappelen, klaver, selderij) onder de APV-Resola-fabriek dan op het referentiegebied zonder zonnemodules. Selderij profiteerde met 12 procent het meest van de testopstelling, wintertarwe won 3 procent, waar klaver een min van 8 procent liet zien. “Wat betreft aardappelen neemt de efficiëntie van het landgebruik met een verbazingwekkende 86 procent per hectare toe”, benadrukt projectmanager Stephan Schindele van Fraunhofer ISE.

We kunnen ervan uitgaan dat de planten het beter hebben gedaan tijdens deze droge hittezomer van 2018 als gevolg van de beschaduwing onder de semitransparante zonnemodules.

Monitoren micro-klimatische omstandigheden

Naast de ontwikkeling van de teelt, opbrengst en opbrengstkwaliteit, verzamelden wetenschappers van de Universiteit van Hohenheim ook gegevens over de micro-klimatische omstandigheden onder en naast de APV-Resola modules. De fotosynthetische zonnestraling onder het APV-systeem was ongeveer 30 procent lager dan op het referentieoppervlak. Naast zonnestraling beïnvloedden de PV-panelen primair de neerslagverdeling en bodemtemperatuur. De bodemtemperatuur onder de panelen was in het voorjaar en de zomer lager dan die van het referentieoppervlak, terwijl de luchttemperatuur gelijk bleef.

In de hete en droge zomermaanden van 2018 was het bodemvocht in de tarwevoeding onder de PV-panelen hoger dan in het referentiegebied. In de wintermaanden en andere culturen was het echter lager, door de koude in de grond.

Betere cijfers ondanks extreem droge zomer

“We gaan ervan uit dat de planten beter bestand zijn tegen deze droge hittezomer van 2018 als gevolg van beschaduwing onder de semitransparante zonnepanelen”, zegt agronoom Andrea Ehmann. “Dit illustreert ook het potentieel van de APV-Resola toepassing voor droge regio’s, maar ook de behoefte aan verdere experimenten in andere klimatologische regio’s en met andere gewassoorten”, vult haar collega Axel Weselek aan.

Agro-fotovoltaïek brengt synergie-effecten met zich mee voor de landbouw


De zonnestraling in 2018, op 1319,7 kWh per vierkante meter, was 8,4 procent hoger dan het jaar ervoor. Dit verhoogde de productie van zonne-energie in het oogstjaar 2018 met 2 procent tot iets minder dan 250 MWh, wat overeenkwam met een “uitzonderlijk goed” rendement van 1.285,3 kWh per geïnstalleerde kilowattpiek. Met elektriciteitsopwekkingskosten per kilowattuur is elektriciteit uit een agro-fotovoltaïsche installatie nu al concurrerend met kleine PV-opdaksystemen, en onderzoekers rekenen ook op dalende kosten als gevolg van doorontwikkeling en opschaling.

Agro-fotovoltaïsche installatie nu al concurrerend met kleine PV-opdaksystemen.

Toename van elektriciteitsvraag

Als de zonne-energie direct op het terrein wordt gebruikt, zoals in het geval van de Heggelbach-boerengemeenschap, worden er extra inkomstenbronnen gecreëerd voor landbouwers door synergie-effecten. Het gebruik van elektrische voertuigen wint ook terrein in de landbouw, aangezien de fabrikanten van landbouwmachines Fendt en John Deere de afgelopen jaren de eerste volledig op batterijen werkende e-tractoren introduceerden.

“Als het beleid het toelaat, kan agro-fotovoltaïek het antwoord zijn op de bespreking van de tank of plaat, omdat technisch gezien boeren hun akkerland gelijktijdig kunnen voorzien van hun kernwerkzaamheden (voedselproductie) en door bij te dragen aan zonne-energie om de energietransitie meer ruimte te geven”, zegt Schindele.

Technologie biedt potentieel voor dorre gebieden

De resultaten van de hete zomer van 2018 toonden het enorme potentieel van agro-fotovoltaïsche cellen voor droge klimaten, waar gewassen en teelt kunnen profiteren van de beschaduwing door de PV-modules. De Fraunhofer ISE is al bezig met de overdracht van de technologie naar opkomende en ontwikkelingslanden en met nieuwe toepassingen in verschillende projecten. Een voorstudie door het het Staatsinstituut van Maharashtra, in India, suggereert bijvoorbeeld dat deze toepassing de schaduwwerking en lagere verdamping van tomaten en katoen de teelt tot 40 procent kan verhogen. “In dit specifieke geval verwachten we dat de regio de efficiëntie van het landgebruik bijna zal verdubbelen,” zegt Max Trommsdorff van Fraunhofer ISE, projectleider van de voorstudie.

In een project in het kader van het EU-programma Horizon 2020 onderzoeken de Fraunhofer-onderzoekers en hun partners in Algerije hoe de APV-systemen de waterhuishouding beïnvloeden. Naast verminderde verdamping en lagere temperaturen speelt regenwaterwinning met PV-modules daar ook een rol.

Het project APV-Resola wordt gefinancierd door het federale ministerie van Onderwijs en Onderzoek en FONA – Forschung für nachhaltige Entwicklung (onderzoek voor duurzame ontwikkeling). Het is een gezamenlijk project van Fraunhofer ISE, BayWa r.e. Solar Projects GmbH, Elektrizitätswerke Schönau, Hofgemeinschaft Heggelbach, Karlsruhe Instituut voor Energie, Regionale alliantie Bodensee-Oberschwaben en de universiteit van Hohenheim. (bron foto: BayWa r.e.)

Voeg een windturbine toe aan uw energie-opwek

Voor de elektriciteit die nodig is tijdens de wintermaanden, is een privé windturbine bij een agrarisch bedrijf ideaal. Windturbines produceren in de winter de meeste elektriciteit waar zonnepanelen dit in de zomer doen. Samen maken ze de ideale combinatie om een agrarisch bedrijf het hele jaar door van elektriciteit te voorzien. Vooral in streken met voldoende wind is het opwekken van windenergie veel voordeliger dan het opslaan van zonne-energie in batterijen.

Bekijk al onze turbines en mogelijkheden


Wilt u weten wat de beste groene energie-oplossing is voor uw bedrijfsvoering?

Bent u nieuwsgierig hoe wij u kunnen helpen om uw energievoorziening ‘groener’, stabieler en goedkoper te maken? Vul het formulier in en wij maken een persoonlijk voorstel voor uw situatie.


De belangrijke rol van de landbouw in de transitie naar 100% groen.

Welke rol spelen agrariërs in de levering van duurzame energie? Zelfvoorzienend zijn is één, maar kunnen zij ook als producent van duurzame energie een voorname rol gaan spelen? De mogelijkheden zijn er zeker, echter moet er wel steun komen wanneer men deze rol ziet weggelegd voor de gemiddelde landbouwer.

Naar schatting leverde de agrarische sector in 2018 al meer dan 15% aan groene energie voor de huishoudens in ons land. Nederland is zich steeds meer bewust van het feit dat onze groene energie nauw samenhangt met de duurzame kwaliteiten van de agrarische sector. Echter zijn we er nog lang niet wanneer het verduurzaming van Nederland betreft. De komende jaren zullen er nog veel meer kansen ontstaan en benut moeten worden om Nederland en met name de agrarische sector, te vergroenen.

Energieleveranciers zijn zich bewust van het aandeel dat boeren hebben in de verduurzaming van Nederland.

Opwekker, verbruiker en leverancier

Ook Energieleveranciers zijn zich bewust van het aandeel dat boeren hebben in de verduurzaming van Nederland. Men verwacht dat in de komende jaren minimaal 25% van onze duurzame energie afkomstig is van agrariërs. Met de inzet van bestaande en de komst van innovatieve mogelijkheden om zelf energie op te wekken, kan dat percentage zelfs nog veel hoger uitvallen.

Veel agrariërs gebruiken de opgewekte energie in eerste instantie voor het dagelijks verbruik in hun eigen bedrijf. De energie wordt gebruikt voor machines, de productie van gewassen, het koelen van opslagcellen en het voeren van dieren. De energie welke niet wordt gebruikt, het overschot, wordt via het net terug geleverd aan energiebedrijven. Deze energiebedrijven kunnen de terug geleverde energie op hun beurt weer verspreiden naar derden zoals particulieren en andere bedrijven. Op deze manier is de wisselwerking tussen enerzijds de agrarische sector en anderzijds de energieleveranciers weer een stapje verder.

Duurzaam delen op lokaal vlak

Om het lokale aspect uit te lichten zijn er al plannen waarbij agrarische energie-producten nabijgelegen woningen direct voorzien van duurzame energie. Nu zijn deze plannen nog kleinschalig, zodat alleen de directe omgeving kan worden voorzien. Met alle duurzame technische innovaties in het vooruitzicht zal dit gebied al snel opgeschaald worden.

Tijdens de wintermaanden hebben veel agrarische bedrijven elektriciteit nodig maar is er weinig zon. Omdat het in de winter en ook herfst meer waait dan in andere jaargetijden biedt een windmolen een prima oplossing.

Combineer Wind en Zon

Een mooi voorbeeld waarbij een agrarisch bedrijf zo goed als energieneutraal is en tevens als energie-producent kan worden beschouwt is een zogenaamde wind-zon combinatie. Veel boeren hebben naast een windturbine tegenwoordig ook zonnepanelen op één of meerdere schuren liggen.

Tijdens de wintermaanden hebben veel agrarische bedrijven elektriciteit nodig maar is er weinig zon. Omdat het in de winter en ook herfst meer waait dan in andere jaargetijden biedt een windmolen een prima oplossing. In de lente en de zomer is het net andersom, de zon schijnt vaker en feller, zodat tijdens deze periodes de zonnepanelen uitkomst bieden.

Zowel bij een overschot aan energie opgewekt door zon als wind kan er terug geleverd worden aan het net, waardoor andere partijen weer kunnen worden voorzien van duurzaam opgewekte energie. Op deze manier voorziet de boer niet alleen zichzelf maar ook derden van groene stroom.

Energy sources C3 EN


Een ander voordeel van een zon-wind combinatie is het zogenaamde ‘cablepooling’. Wanneer men voor de aanleg van een zonnedak een speciale kabel dient aan te leggen is de dikte van deze kabel vaak gebaseerd op de piek-momenten van het zonnedak welke slechts een aantal keren in de lente en zomer voorkomen. Op andere momenten, vooral in de zonarme maanden, wordt deze kabel niet optimaal benut.

Wanneer de zonnepanelen vlakbij een windturbine liggen kunnen beide duurzame bronnen via één kabel worden aangesloten. De momenten dat zowel zon als wind volop aanwezig is en de kabel voor een uitdaging stellen zijn uitermate zeldzaam en de productinstallaties zijn daar goed op af te stemmen. Zo kunnen zowel kleine als grote producenten van zonne-en windenergie veel geld besparen en tevens de aangelegde kabel optimaal benutten.

Wanneer de zonnepanelen vlakbij een windturbine liggen kunnen beide duurzame bronnen via één kabel worden aangesloten.

Niet alleen de producenten maar ook de netbeheerders zullen, gezien alle investeringen welke de noodzakelijke aanpassingen in het net met zich meebrengen, erbij gebaat zijn dat de kabels zo efficient en rendabel mogelijk benut worden. Minder kosten aan netverzwaring en onderhoud voor de netbeheerder, een slimmer gebruik van de bestaande infrastructuur en een toenemende CO2 besparing; het duurzame mes snijdt aan meerdere kanten.

De techniek staat voor niets en alle innovaties die de komende jaren op zullen duiken zorgen ervoor
dat er voldoende mogelijkheden zijn voor agrarische bedrijven om nog eenvoudiger energieneutraal te worden en tevens derden te voorzien van duurzame energie.

Delen is vermenigvuldigen

Het is vooral een financiële discussie. Investeringen in verduurzaming zijn vaak groot en alles uit eigen zak betalen is vaak niet mogelijk. Daarom is medewerking vanuit de overheid met behulp van subsidies een must. Krijgen de boeren de benodigde hulp om daadwerkelijk te investeren in mogelijkheden waardoor men naast zelfvoorzienend ook in staat is groene energie te leveren aan derden? Het probleem van de overheid, de uitputting van onze huidige grondstoffen voor het opwekken van energie, zou voor een groot deel opgelost worden.


The essential role of agriculture in the transition to 100% green.

What role do agriculturists or farmers play in the supply of sustainable energy? Being self-sufficient is one thing, but can they also play a major role as a producer of sustainable energy? The possibilities are available, but support must be provided when the average agriculturists has to become an energy supplier.

It is estimated that in 2018 the agricultural sector already supplied more than 15% of green energy for households in our country. The Netherlands is increasingly aware of the fact that our green energy is closely linked to the sustainable qualities of the agricultural sector.

However, we are not even close when it concerns reaching our sustainable targets. In the coming years, many more opportunities will arise and must be exploited to make sure, the Netherlands and especially the agricultural sector, will become more sustainable.

Energy suppliers are also aware of the share farmers have in making the Netherlands more sustainable.

Producer, consumer and supplier

Energy suppliers are also aware of the share farmers have in making the Netherlands more sustainable. It is expected that at least 25% of our sustainable energy will be produced by farmers in the coming years. With the use of existing and the arrival of innovative possibilities to generate green energy yourself, that number will undoubtedly rise

Many farmers initially use the energy generated on regular basis in their own business. The energy is used for machines, the production of crops, the cooling of storage cells and for feeding the animals. The energy that is not used, the surplus, is distributed to energy companies via the grid. These energy companies can distribute the energy from the farmers to third parties such as private households and other companies. In such a way, the interaction between the agricultural sector and the energy suppliers is a step further.

Sustainability at local level

To highlight the local aspect, there are already plans in which agricultural energy producers provide nearby households with sustainable energy. At the moment these plans are still small-scale, so that only the immediate environment can be provided. With all sustainable technical innovations in prospect, the size of this area will soon be scaled up.

During the winter months, many agricultural companies need electricity but the available sunshine is scarce. As there is more wind in winter and also in autumn than in other seasons, a wind turbine offers a great solution.

Combine Wind and Solar

A good example in which an agricultural company is practically energy neutral and can also be regarded as an energy producer is a so-called ‘Wind-Solar Combination’. Nowadays many farmers own a wind turbine and also add Solar-panels on one or more of their shed roofs.

During the winter months, many agricultural companies need electricity but the available sunshine is scarce. As there is more wind in winter and also in autumn than in other seasons, a wind turbine offers a great solution. In the spring and summer, it is the other way around. The sun is shining more often and brighter, so that the solar panels offer a perfect solution during these periods.

The surplus generated by wind or sun can be distributed to the grid. In this way, other parties can be supplied with sustainably generated energy as well. The farmer provides himself and other (third) parties with sustainable energy.

Energy sources C3 EN

Cable pooling

Another advantage of a Wind-Solar combination is so-called ‘Cable pooling’. If a special power cable is necessary for the construction of a Solar PV installation, the thickness of this cable is often based on the peak moments of the PV installation which occur only a few times during spring and summer. During months with less sun hours, this cable is not used optimally.

When the Solar PV is installed near a wind turbine, both sustainable sources can be connected via the same cable. The moments when both sun and wind are fully present are extremely rare and both product-installations can be monitored if necessary. In such a way, both small and large producers of solar and wind energy can save a lot of money and also make optimal use of the installed cable and grid connection.

When the Solar PV is installed near a wind turbine, both sustainable sources can be connected via the same cable.

Not only energy producers but also the network operators will, given all the investments that entail the necessary adjustments to the network, benefit from the cables being used as efficiently and profitably as possible. Fewer costs for network reinforcement and maintenance for the network operator, smarter use of the existing infrastructure and increasing CO2 savings; multiple benefits.

The future of technology is endless and all the innovations that will pop up in the coming years ensure that there are sufficient opportunities for agricultural businesses to become even more energy-neutral and also to provide others with sustainable energy.

Sharing is Caring

It is primarily a financial discussion about this topic. Investments in sustainability are often large and financing everything with equity is often not possible. That is why government support in the form of incentives is a must. Will farmers receive the support they need to actually invest in opportunities that enables them to supply green energy to third parties in addition to being self-sufficient? The problem of the government, the depletion of our current raw materials for generating energy, would be solved to a large extent.

wind and sun

Solar and Wind energy, the perfect match

Combining wind and solar energy, the big picture

Solar panels are very popular and are becoming cheaper by the day. Not only are they easy to place on roofs or vacant pieces of land, they are one of the least intrusive renewable technologies available on the market at the moment. When placed on top of buildings their placement and size making them almost invisible. Because of all these positive traits of solar panels. we frequently hear the question: ‘’Why should we purchase a wind turbine when we can also have solar panels?’’

Solar panels are a great source of renewable energy, they can be put on roofs and pick up electricity during daytime. But unfortunately the sun goes down every day. Even in countries where the sun is at full strength, windmills are an excellent addition. Why? The answer is surprisingly simple: for all the hours that there is insufficient sun.


Solar can’t provide the energy peak needed when most households do their chores within the same part of the day.


In countries near the equator the sun is at its fullest strength but actually only shines half the time. This will supply electricity for the daytime peak where all offices and factories run. At noon people go home from work and use a lot of home utilities to comfortably enjoy their leisure time. Solar can’t provide the energy peak needed when most households do their chores within the same part of the day. The combination of sun and wind energy can ensure everyone to enjoy their day to the fullest. In this blog I will explain how these different renewable sources should be deployed together in perfect harmony.

The energy consumption or “load”  

The daily energy consumption of households is as follows:Energy sources grid@4x

This graph represents the energy load of a small community. As you can see, the peak of energy demand is during the evening. This peak is caused by the fact that during the day, people are often at work or engaged in other outdoor activities. In the evening everyone often starts cooking food at the same time, turning on the air conditioning, home media systems, dishwasher, laundry machine and the lights.

In the image above we assume that no sustainable energy is used. The energy consumed in this case is obtained entirely from the grid. In many countries this grid is supplied by fossil fuel-fired plants, which is not only a “dirty” solution, but also an expensive one. In addition, being dependent on the central grid is also dangerous when there is a power outage due to external reasons and can’t be repaired immediately. This will have devastating consequences for public health, social security and businesses, as were seen after Maria hit Puerto Rico. The hidden losses of a power outage are enormous. Want to more about the unforeseen consequences, read this article. More and more authorities choose to privatize the power utility market and let businesses and communities be self-reliant in their energy needs.


In order to generate enough electricity to power houses both during the day and store it for the consumption during the night, you would need twice as many solar panels, and even more batteries to provide renewable energy all day.


The supply of sunlight, and the times of shortage

The biggest “shortcomings” of solar panels are now quite clear. When the sun is down, no energy is generated by the panels, and when it is cloudy, less will be generated. The image below clearly shows why this is a problem. Most of the energy is generated during the day, where it is not quite as necessary as in the evening. This means that most of the energy will have to be stored in order for it not to go to waste, and to have enough energy to power all the homes in the evening and night. But this brings with it its own problems, the main ones being storage efficiency and cost.

Energy sources 2@4x

In order to generate enough electricity to power houses both during the day and store it for the consumption during the night, you would need twice as many solar panels, and even more batteries to provide renewable energy all day. This is because quite a bit of power lost when storing electricity, and lose even more when it is later distributed. Not to mention the costs of all the batteries needed to store enough energy to power a small community throughout the night. Furthermore, this solution requires the solar panels to generate enough electricity all the time, which as mentioned is dependent on how cloudy the skies are during the day. By utilizing several different energy sources, this dependency on the weather is drastically reduced!


By adding wind to the energy generation a much smaller-scale storage source (for example, a battery or hydrogen) is needed.


Wind fills the substantial gaps

The solution is to combine renewable sources. The big plus of wind energy is that it is a more constant source of energy. This allows you to properly cover the energy gaps during the day! In areas with sufficient wind, the generation of wind energy is several times cheaper than storing solar energy in batteries. A good example are the islands in the Caribbean. The Lesser Antilles for example have lots of sun and a strong constant wind, an ideal situation for setting up an all renewable energy solution. I hear you think, and what if a hurricane comes by and blows away the wind turbines? We came up with a solution for that. We designed an in-board-hoisting-crane that can lower its own rotor and blades before the hurricane arives, no external hoisting cranes will be imported to do so. 

Below you find a graph where a combination is made of wind and solar energy. By adding wind to the energy generation a much smaller-scale storage source (for example, a battery or hydrogen) is needed. The surplus from the afternoon can be stored and re-used when necessary. This battery capacity can be much smaller and cheaper in comparison to when you were only installing solar panels. In short, by combining in sustainable energy sources, a total green solution is a lot closer!

Energy sources 1@4x

On locations with less sun you can also reduce your fossil fuel consumption dramatically by adding a turbine to your local infrastructure. My colleague Wim Joosten has previously written an interesting blog about adding a wind turbine to a network that acts on (bio) fuel-fired generators, Which can be read here. 

This article gives an interesting insight into hybrid grid solutions, where a grid gets the best out of both technologies: the reliability of diesel generators, and the effective and costless energy from wind turbines.

Want to find out what solution is best fit for your scenario?

Are you curious whether this method can help you to make your energy supply ‘green’, more stable and cheaper? Just contact us, we would be happy to help you and to analyse which combination of energy sources suits your situation best.