There is no legal framework for effects on the environment of large-scale solar parks. Provinces or municipalities can include guidelines in their policy that solar parks must meet. These might concern, for example, the effects of solar projects on ecological values, land use and soil.
Bosch & van Rijn carries out acoustic analysis for wind projects with the aid of a specialised software package. We determine whether a planned wind turbine or wind farm meets the national noise emission standards and if mitigating measures are needed to fulfil the standards.
Every wind turbine or wind farm must comply with the statutory noise emission standards of 47 dB Lden and 41 dB Lnight. Lden stands for the Level day, evening, night, or the time-weighted annual average noise level during the day, evening and night period. In the evening, a correction of +5 dB applies and at night this value is +10 dB. Low-frequency sound is also covered by this standard. The limit values of 47 dB Lden and 41 dB Lnight are weightings between space for an activity and limitation and nuisance to local residents.
In addition to the studies for planned wind turbines, Bosch & van Rijn can also carry out acoustic analysis (also called emission term studies) for existing wind turbines. By using production data, wind speeds and source strength, Bosch & van Rijn can calculate whether 47 dB Lden and 41 dB Lnight are exceeded in noise-sensitive objects.
The moving blades of a wind turbine can cause annoying shadows on nearby homes. The legal standard for the permissible shadow flicker duration on sensitive objects is somewhat complicated. On average, shadow flicker may not occur more than 17 days per year for 20 minutes per day. To calculate based on this standard, we assume a maximal shadow flicker duration of 5 hours and 40 minutes annually. In practice, this is stricter than the current standard.
Bosch & van Rijn uses a specialised software package to carry out shadow flicker calculations for wind projects. We can determine for planned wind turbines or wind farms whether the legal standards for shadow flicker are met. With this analysis, we can also determine if turbines must be paused briefly to meet the standard. A standstill facility is contained in the control software of wind turbines. The software only switches the turbine off if shadow flicker occurs.
In addition to testing in terms of the legal standard, on request we can also identify shadow flicker duration on nearby objects.
There are various legal frameworks with which people, high-risk installations and infrastructures are protected against the potential risks of wind turbines. For example, the site-specific risk for a vulnerable object located outside the facility, caused by a wind turbine, may not exceed 10-6 per year and for a somewhat vulnerable object 10-5. For high-risk installations, the increase in catastrophic failure frequency may not increase by more than 10% according to the Risk Zoning Wind Turbines manual. There are strict regulations for pipelines from Gasunie, and for trunk roads, Rijkswaterstaat has established standards.
Bosch & van Rijn conducts safety investigations to determine whether the risks to people and the infrastructure are acceptable. For this purpose, Bosch & van Rijn has developed its own calculation model that can calculate per location and turbine type:
- What distance must be maintained for objects (gas pipelines, offices, transport routes, etc.).
- What are the turbine-specific risk contours (e.g. 10-5 and 10-6 contour)?
- What the chance of hitting a nearby installation or building is.
- What the Person-related (PR), Individual Passer-by (IPR) and Social (MR) risk are.
The combination of mathematical expertise with legal and planning knowledge enables us to calculate risks, interpret them and, if necessary, develop solutions.
The Nature Conservation Law (Wet natuurbescherming) protects Dutch nature reserves, and plant and animal species. A differentiation is made between regional protection and species protection. Provinces establish the nature policy and are responsible for issuing permits and exemptions.
A wind turbine or wind farm has ecological effects both during the construction phase and during the use phase. The effects in the construction phase are often temporary and can be remedied easily. During the use phase, the ecological effects are mainly bird and bat collisions.
A nature assessment must always be carried out before the realisation of a wind turbine or wind farm. The complexity and scope of such a study depends on the project. Bosch & van Rijn has the expertise to assess ecological studies and process them in the environmental impact assessment.
The arrival of a wind farm or a solar project will affect the experience of the landscape. Provinces and municipalities frequently have guidelines concerning how a wind farm or solar park must be fit into the landscape.
Based on our extensive experience with project development, we can draw up a landscape assessment of wind farms and solar parks. If the effects on the landscape are complex, we call on landscape architects for assistance. Bosch & van Rijn has developed a visualisation tool which allows for the future wind farm or solar park to be shown and experienced in Virtual Reality. We also use these visualisations when assessing effects on the landscape.
Other effects can also occur. For example, an increase in paved surface influences water. Whether this requires further rules or permits differs from one province, municipality or water board to the other.
There may also be effects on the soil condition, because work is carried out involving the soil or the ground is overshadowed by solar panels. Generally, soil quality causes no problems for the development of a wind farm.
It is possible that archaeological finds are expected at the location of a future wind farm or solar park. Only if archaeological values are to be expected must archaeological studies be carried out before a wind farm or solar park can be built.