Green energy

Biogas is created by fermentation of organic substances. In nature, this fermentation can happen at the bottom of bodies of water or in bogs, for example, or even in the stomachs of ‘ruminant’ animals (e.g. cattle or sheep). At a biogas plant, the controlled fermentation process takes place in fermentation tanks known as ‘digesters’. These large tanks contain the organic substrate, which is decomposed by methane bacteria. This process, called anaerobic digestion, produces a mixture of gases. Roughly 55% of it is methane, an energy-rich biogas. The digestate, that is left over after digestion, can also be fully reused as a natural, nutrient-rich fertiliser.

There are four stages during the biogas formation process. During hydrolysis or the liquefaction stage, the starting materials (fats, carbohydrates and proteins) are split into their fundamental chemical elements (such as fatty acids, monosaccharides and amino acids). During acidogenesis or the acidification stage, the hydrolysed materials are broken down into organic acids. The third stage, acetogenesis or acetic-acid production, sees the microorganisms transform these materials into hydrogen, carbon and acetic acid, the precursor materials to biogas.
Methanogenesis, or methane production, forms the final stage of the process. Without oxygen( ‘anaerobic’ conditions), the methane bacteria first turn the acetic acid into carbon dioxide, hydrogen and methane. The carbon dioxide and hydrogen subsequently become water and methane. Then, before further use, the biogas is desulphurised, purified and upgraded to the relevant plant demands. If you’d like to find out more about modern biogas plant construction and biogas technology, then we would be delighted to explain the details to you in a comprehensive information and consultation session.

In Germany, roughly 900,000 hectares of maize is farmed for biogas plants, which is about equivalent to the amount of land used for maize farming in the late 1980s. Maize grows to be very tall right before it is harvested. It’s difficult to oversee and hence is seen as something “quite dominant”, though its size also offers a benefit: maize produces more biomass per hectare than almost any other crop. What’s more, it requires little water and fertiliser, and yet still forms a great amount of gas during fermentation. The farming of bioenergy crops has also had a significant part in stabilising incomes in the agricultural sector. Farmers benefit from higher profits when they sell their harvest, while biogas plants offer many farmers a secure foundation for generating income in times when milk and meat prices are low. (Source: Fachverband Biogas e.V.)

The electrical output of a biogas plant ranges from roughly 75 kW (a small plant) to several megawatts (a large plant). The amount of power that a plant generates depends on the amount of biogas produced. A farmer can expect to obtain 400 to 500 m³ of biogas per livestock unit per year. One hectare of pasture grass can produce up to 7,000 m³ of biogas per year and energy-rich plants such as turnips or maize can produce even more. This means that building a biogas plant not only profits the climate and environmental protection, but is also a sustainable investment in a farm’s future viability and profitability.

Producing biogas requires a permit. If you wish to operate a biogas plant, you need to be familiar with the legal requirements and complete all the necessary formalities before starting construction. We’re happy to support our clients with their applications for permits. We can boast over 20 years of knowledge from applying and developing these systems, so we’re closely familiar with the individual steps and processes. We clear a path through the administration & government jungle of forms so that your biogas plant is fully compliant with applicable law and you can take full advantage of all potential funding and subsidies granted by the state and the nation.

Once the preparations are complete, you can get started building your biogas plant at your intended location. We perform all the required inspections and professional acceptance testing before putting it into routine operation. If desired, we can also make a separate arrangement to guarantee a specific electricity, gas or heat yield from your plant, giving you full certainty for your planning and finances.

Using our modern process control system, BioControl, we ensure that biogas plants always perform at their best potential and at an optimal profitability. The software was developed by experienced bioconstruct technology specialists and can also be retrofitted to older biogas plants. It can help you to configure your plant perfectly to your needs (e.g. for an on-demand-based electricity generation) and enjoy a precise overview of individual operational processes at all times.

Unfortunately, animal waste and slurry can’t be put straight into vehicle fuel tanks (just yet). Nevertheless, there’s an alternative that’s just as genius: our biogas plants digest slurry and manure and produce biogas from them. The main products created from this are carbon dioxide and methane. These two are separated from each other and purified using biogas upgrading systems. The carbon dioxide is then purified again and compressed. The end product is ready to dispense into bottles and be transported to soft drink bottling lines to carbonate beverages. Alternatively, it’s also possible to make dry ice – which is already done at our Crofthead biogas plant (see our testimonials).

The methane embarks on an even-longer journey. It’s usually fed into the gas network at the same location as the biogas plant. Then, at any other point in the gas network, an equivalent amount is extracted back out of the network and conveyed to a liquefaction facility that turns the biomethane into bio-LNG (liquefied natural gas). Heavy goods vehicles can use this as fuel and drive up to 1,000 km per tank of it (compared to roughly 1,500 km on diesel), making it an excellent alternative to diesel. The best part is that both the carbon dioxide and LNG can be produced in an environmentally friendly way, while generating and marketing them together with CO2 certificates provides for great profits. This creates a perfect synergy between economy and environment.

bioconstruct plans, builds and maintains plants for farms, medium-sized plants for community use and waste-to-energy plants for industrial use. We have the right technical solution ready for any type of input material or we can create a solution together with our partners. When it comes to utilising biogas, we offer cogeneration and ORC plants as well as biomethane upgrading plants and technology for further processing of the gas. Accordingly, we can generate valuable fuels such as CNG or LNG out of biomethane and even make good use of the carbon dioxide from biogas.

Wind turbines are demanding high-tech components. Despite that, dismantling them and recycling their components has now become a routine matter, as companies in the waste industry can confirm. There are companies that offer straightforward solutions for a cost efficient recycling of wind turbines.

Modern wind turbines are almost fully reused, with 80 to 90 per cent of the components in terms of its weight being recyclable. This is due steel and concrete making up over 80 per cent of a wind turbine. The concrete parts of the foundation can be processed and be used as recycled concrete for new roads. The steel segments are returned to the steelwork factories as a secondary material. Recycling the rotor blades is probably the most-difficult part due to their composition out of fibreglass, carbon fibres and other plastics. If they can’t find another life cycle in a secondary market – usually outside of Europe – they are incinerated by specialised companies and processed for use as a secondary material.

The incineration process involves the rotor blades being crushed, metal parts such as lightning arresters being removed and the leftover product then being burned. The remaining ash, which is less than 30 per cent of the volume of the original material, can be used as a substitute for other raw materials in the cement industry. Processing 1,000 tonnes of fibreglass – the same type used in the automotive, shipping and aviation industries – in the manner just described above, can prevent the consumption of about 450 tonnes of coal, 200 tonnes of chalk and 200 tonnes of sand. This is overall a recognised process: Bremen-based company neocomp GmbH, for instance, recently received the GreenTech Award for this process.

The manufacturers of wind turbines have also set zero-emissions targets for themselves and are endeavouring for an European-wide circular economy. They are continuously investing in research projects and in the optimisation of production and recycling processes. The results are documented in publicly available sustainability reports. (Source: Bundesverband WindEnergie e.V., 2021)

People are surrounded by modern technologies each and every day, not only in towns and cities, but also in their private households and working environments. However, wind energy is one of those technologies that have a highly visible presence in the landscape. This is why people who live nearby wind turbines ask – quite understandably – if wind turbines near residential areas have an impact on people’s health.

There are various studies and reports that debunk these fears. Studies by Germany’s Nature and Biodiversity Conservation Union and various state environment agencies prove that noise in the direct vicinity of wind turbines does not reach a level which is anywhere near concerning for people’s health. Just like choppy wind, surf from the ocean or passing cars, wind turbines also emit noise at very low frequencies, referred to as ‘infrasound’. This infrasound consists of very low tones with a frequency of less than 20 hertz (Hz). Humans cannot normally perceive such frequencies, though some neighbouring residents fear that they can be harmed by infrasound exposure.

Nevertheless, long-term studies show that only a small portion (5 per cent) of people who live in the direct vicinity of wind turbines report symptoms such as headache or sleep disruption. A long-term study by the VTT Technical Research Centre of Finland concluded by saying ‘No evidence of health effects of wind turbine infrasound was found’. To explain the allegedly frequent occurrence of symptoms nearby the wind turbines, the study suggested that they were the result of a ‘nocebo effect’ (analogous to a placebo effect), where influences that are not actually harmful to the human body end up having a negative effect on people’s health because these people think the influences have a negative effect. Symptoms caused by other things can also be incorrectly associated with wind turbines. The infrasound from wind turbines can be contrasted against the infrasound levels found in day-to-day situations, such as inside a saloon car driving at 130 km/h. Such level is much higher than those of a wind turbine 150 metres away. The studies are backed up by a judgement made by the Würzburg administrative court in a case regarding the harmlessness of noise emissions from wind turbines. (Source: Bundesverband WindEnergie e.V., 2021)

Many wind energy projects attract criticism because the wind turbines are getting bigger and taller. Fifteen years ago, the maximum height of a turbine has been 100 metres. These days, they reach up to 250 metres. The simple fact is that there is more wind at greater heights, with the yield increasing by 1 per cent (approximately) for each additional metre that the hub rises. The higher yields from the wind turbines not only benefit their operator, but also helps to protect our nature and benefits our society as a whole. That’s because the operator can sell its power at significantly more-affordable prices thanks to the increased yields from its turbines, and that means the financial support needed for a wind turbine is reduced to a minimum. Furthermore, the higher yields allow the turbines to be shut down for longer periods to minimize affection of local residents by noise and shadow flicker. Wind turbines are even shut down during breeding seasons to protect sensitive bird species such as storks, buzzards and red kites, reducing the risk of collision significantly. These things wouldn’t be possible without the financial buffer provided by a tall wind turbine.

Today’s wind turbines feature a direct connection to the power grid; the electrical energy produced is transferred and fed onwards using power electronics. The peak power of a contemporary onshore wind turbine averages between 3 to 6 megawatts. Offshore turbines are significantly bigger at 6 to 10 megawatts, however these plants are way more expensive to build.

Wind turbines are a catalyst for the energy revolution, with many countries supporting their construction and operation through feed-in tariffs and legally mandated targets for wind energy development. The electricity generation costs are an important factor when comparing solar photovoltaic systems, biogas plants and wind turbines. These costs include all the expenses for generating power from the renewable source of energy, for example the costs to build a system and operate it. Put in context with the power produced by the system, the electricity generation costs say a lot about a system’s cost-effectiveness.

The latest studies show that renewable energies have become competitive. A new solar system or wind turbine, positioned at the right location and backed with a carefully planned financing concept, will already operate more economically today than a new power station fired by fossil fuels- without harming the environment!

When it comes to wind turbines, our focus is on project development, planning, providing the infrastructure (cabling, earthworks and foundations) and financing. We’ll be at your side for the entire journey, from the initial idea and getting permits and funding to managing the wind turbine’s profitable operation. We’ll answer your questions about the opportunities of a given site, for financial support and feasability assessments. We’ll help you to develop a profitable new wind energy project as well as to optimise existing turbines and wind farms. When you come to us, you can rest assured that we’ll remain your point of contact even after construction is finished. For instance, we still administer the very first community-owned wind farm we built back in 2001- with over 150 satisfied invested locals.

Get in touch with us to on-board a team of dedicated experts for your project development and transform your idea and planning into a successful and sustainable result. We’d be happy to set up a phone call or personal meeting so we can explain to you all the details surrounding site analysis, turbine construction, engineering and modern wind power financing.

When solar photovoltaic systems are built in open spaces, it’s usually in such areas that are designated as ‘unfavourable’ land. Unfavourable might be, for example, low-yield areas with poor soil or not enough rain. Even in good spaces, system owners might build ‘agrivoltaic’ systems, which consist of panels in a vertical angle that allows farmers to continue using the land , e.g. as a pasture. More details on this can be found on the website of our partner, Next2Sun GmbH.

Photovoltaics (PV) , is planned to become a key pillar of the energy revolution. It offers massive potential, and not only because with rooftops and open areas huge amounts of space are suitable for solar PV systems. The main argument to make even more use of solar photovoltaics is that this technology has become enormously more cost-effective.

Yes, they can! Flowering plants and herbs can be grown between panels to provide an ideal habitat for bees and other insects. At some of our photovoltaic sites, there are even sheep that graze in these spaces. The animals are happy and content to graze beneath the panels when it’s windy or hot outside, which has a pleasant side effect of stopping the vegetation around the system from growing too tall.

The prices for solar PV panels decreased by 90 per cent (!) between 2010 and 2021. The nowadays attractive investment costs, coupled with relatively low operating and maintenance costs, have resulted in solar power being able to be generated for less than €0.05 per kWh. This is cheaper than any conventional power plant if you consider carbon emissions in your calculations.

For this reason, we’re expecting a solar-power boom over the next decade. Not only in sunbathed areas such as southern Europe, but also and especially in places that consume lots of electricity, like densely populated Germany for example.

Farmers and community representatives often ask if it would be better to use a hectare of farmland to install a solar photovoltaic system rather than growing plants like maize for biogas. There’s good reason to ask this, as a solar PV system produces 32 times as much power per hectare compared to biogas. However, such a figure is only half of the truth. In addition to power, biogas plants produce an equal amount of heat. Accordingly, the energy yield from a solar PV system is only 16 times greater than biogas. This is still a very large yield and would make you think that solar power is much better than biogas. Yet for as long as there isn’t an affordable method for storing solar PV power, we need to use the electricity from solar PV systems at the time it’s produced, which is usually around midday during summer. Biogas power, on the other hand, is always available and can even be generated on a demand-based basis, i.e. whenever supply is running low and there are clouds in the sky (or at night). This is what makes biogas power so valuable and suggests that the two forms of energy are equally important. The power from PV is cheap but not reliable, whereas the power from biogas is reliable and therefore extremely valuable!

bioconstruct concentrates on planning, constructing and overseeing large systems on commercial rooftops and open, non-built-up areas. The ideal open spaces are meadows and fields beside motorways and railway tracks as well as farming areas that have low yields when used for food or feed production. Unused industrial estates and former airports are also ideal for conversion.