Questions & Answers
Modern Tier one quality solar panels that are correctly installed and tilted are built to withstand hailstones of a certain size and velocity. Manufacturers test their panels for durability and impact resistance, and they usually provide information about the specific hail rating for their products. This rating indicates the size and speed of hailstones that the panels can withstand without significant damage.
If the glass cover over the panel's cracks, the underlying soil could be contaminated with lead (however, lead-free panels are now available but may not be economically viable yet). These small amounts of contaminants tend not to leach. Instead, they bind to soil and runoff when sediment is eroded. However, there is a moderately low risk of sediment loss to waterways if the solar farm is managed well. As the solar panels are wired in series of up to XX panels, a broken panel would cause the whole XX panels to stop production and trigger an alarm.
In addition to the above, any cracked solar panels are quickly rectified as most Solar farms have stringent Operations and Maintenance contracts, including onsite and remote monitoring (part of the lending requirements to fund solar farm construction). In addition, spare panels are kept on site for such events and will be swapped out within a few days of breakage. Also, when a panel breaks, the glass sits on the vinyl back sheet of the panel, and very little falls onto the ground. Therefore, the risk of glass or panel components being washed away with stormwater and into drains is highly unlikely.
For additional information:
A comprehensive set of guidelines available from an independent organization has been put together by the International Energy Agency:https://iea-pvps.org/publications
The “Human health risk assessment methods for PV Part 2: Breakage Risks”
Hail Resistance
Solar farms built in hail-prone areas should be procuring PV solar panels that are designed and tested in accordance with the IEC performance standards. These go above and beyond the requirements covered by AS/NZS standards:
- IEC 61730-1: Photovoltaic (PV) module safety qualification - Part 1: Requirements for construction https://webstore.iec.ch/publication/25674
- IEC 61215-1: Terrestrial photovoltaic (PV) modules - Design qualification and type approval - Part 1: Test requirements https://webstore.iec.ch/publication/61345
More useful links related to extreme weather management for solar panel installations:
https://eif-wiki.feit.uts.edu.au/_media/solar_panel_iec_standards_testing.pdf
https://www.nrel.gov/docs/fy22osti/81968.pdf
Solar farms have the potential to contribute to heat formation, although their overall impact is generally lower compared to urban areas or industrial zones. Heat islands occur when a specific area experiences significantly higher temperatures than its surrounding regions due to human activities and the built environment.
Solar farms generate heat through two primary mechanisms:
Absorption and re-emission of sunlight: Solar panels absorb sunlight to produce electricity, but a portion of that energy is converted into heat. While modern solar panels are designed to convert sunlight into electricity efficiently, some heat is inevitably generated. This localised heat generation can lead to a slight increase in temperature within the solar farm.
Modification of land surface:
Installing solar farms often involves clearing vegetation and altering the land surface, which can impact the area's energy balance. Vegetation plays a role in temperature regulation through transpiration and shading, but these cooling effects diminish when replaced by solar panels. As a result, the absence of vegetation cover can contribute to localised warming.
It's worth noting that solar farms typically cover large areas and are often situated in open, rural regions where land use is less dense compared to urban areas. Therefore, their contribution to heat islands is usually much lower than that of cities or urbanised regions with extensive infrastructure, concrete, and asphalt surfaces.
Furthermore, solar farms can also provide certain cooling benefits. Solar panels reduce the amount of sunlight reaching the ground, which can lower surface temperatures compared to bare, sunlit land. Additionally, solar panels absorb and convert solar energy, thereby reducing the amount of energy that would otherwise be converted to heat by other human activities, such as fossil fuel-based power generation.
Solar farms can be designed and managed with specific considerations to mitigate potential heat island effects. For example, incorporating vegetative buffers around the perimeter or interspersing the solar panels with low-growing vegetation can help reduce the heat island effect. Additionally, careful site selection, optimising panel orientation and spacing, and implementing cool roof technologies can minimise any localised temperature increases.
Local Heat Island Creation & Global Warming Effects
The vegetative characteristics of the land use, before and after the solar farm development occurs, plays a key role. Most studies have concluded the heating effects are localized with no overall day-to-day warming effect:
http://www.clca.columbia.edu/13_39th%20IEEE%20PVSC_%20VMF_YY_Heat%20Island%20Effect.pdf
https://www.nature.com/articles/srep35070
This has been translated into state planning guidelines in Australia, such as those published by Victoria:
Furthermore, UNSW was commissioned to put together this report for the NSW Government, which lists technical references:
NSW Government’s recently published Large-Scale Solar Energy Guideline represents the most comprehensive set of guidelines published by the Australian states:
The NREL has published a few reports related to the benefits of adding low-growing vegetation under solar panel installations:
https://www.nrel.gov/docs/fy14osti/60240.pdf
https://www.nrel.gov/docs/fy17osti/66218.pdf
Other resources available that describe the advantages of hybrid land use:
General Setback Distances between PV Solar Farms & Residential Dwellings
As this Australian Government statement describes, “Setback distances for large-scale solar arrays are still largely being developed and refined by state governments” https://www.aeic.gov.au/observations-and-recommendations/governance-compliance
In other jurisdictions further afield (for example), Indiana University’s Environmental Resilience Institute recommends a minimum setback distance of 150 feet (46.3 m):
https://eri.iu.edu/documents/in-solar-ordinance-2020-december.pdf
A new term has emerged called Agrivolatic farming, a concept where both solar power and agriculture share ground rather than being in competition against each other.
While Agrivolatic farming is still in its infancy, there have already been many successful examples of sheep grazing around solar panels, brocolli successfully growing in partly shaded areas and even water harvesting.
Research shows that Agrivolatics has more benefits than just sharing of the land. According to the World Economic Forum “the shade” from the panels protects vegetables from heat stress and water loss.
Solar panels and equipment are not likely to cause a fire. Yet it is important to identify the fire risks of a solar farm and mitigate them effectively.
Like any electrical equipment, the main cause of fires in solar panels is related to faulty installation, electrical faults or malfunctions. For example, damaged or poorly installed wiring can ignite a fire.
However, solar panels and their components are generally designed to meet stringent safety standards, and manufacturers are required to comply with regulations related to electrical safety.
For example, solar panels are tested to withstand high temperatures, humidity, and other environmental conditions, and are required to have various safety features, such as overcurrent protection and grounding.
Furthermore, solar farms are typically designed with fire prevention and mitigation measures in place. For example, fire detection and suppression systems can be installed to detect and extinguish fires quickly, and maintenance schedules can be implemented to ensure that panels and equipment are kept clean and free of debris.
Solar panels contain trace amounts of heavy metals such as lead and copper, which are used in the production of solar cells. However, these heavy metals are typically contained within the solar panel's protective layers, including the glass, backsheet, and encapsulant, which prevent them from leaching into the environment.
“The reports about contamination come from the end of their life. The actual solar panels are not going to leak, it’s like glass in the environment. The lead and the copper are completely encapsulated” - Justin Hodgkiss
Solar power systems themselves do not contribute to noise pollution as they do not have any moving parts that generate noise. The main components of a solar power system, such as the solar panels and the inverter, are designed to operate silently. Although can produce a slight humming noise, but this is generally not audible from a distance and is not considered a significant source of noise pollution.
However, during the installation of a solar power system, there may be some noise generated by construction activities such as piling for the foundations. This noise is typically temporary, confined to day time hours, and is similar to the noise generated during other construction activities.
New Zealand Council resource consents regularly impose a maximum noise limit for solar farms to ensure wildlife and the wider community are not impacted
The visual impact of solar panels depends on individual opinions and the context in which they are installed. While some people may find solar panels visually unappealing, others view them as a symbol of sustainability and renewable energy.
The visual impact of a solar farm has a much less impact than a wind farm, where the consent of wind turbines is highly contentious. For this reason “the visual catchment area for a wind farm can be 20-30 kilometres or more, large solar sites in areas with flat topography have a much more contained viewing audience.”
Solar farms can be designed to minimise their visual impact through vegetation screening around the boundary of the solar farm. Through planting of natives, the biodiversity of the site can be improved.
Solar panels are designed to absorb the sun’s rays rather than reflect them. Standard solar panels add non-reflectance coatings to assist in glare reduction and boosting the efficiency of the solar panels.
Solar farm project plans are also analysed during the resource consent process to mitigate potential glare. Several solar projects worldwide are next to airports with no glare obstruction for pilots.
According to USA’s National Renewable Energy Laboratory (NREL) solar power systems are at low risk of electromagnetic interference (EMI).
Electromagnetic interference (EMI) refers to radio frequency (RF) emissions that can affect nearby communication devices and navigational aids.
However, USA’s Federal Aviation Administration (FAA) has said that EMI from solar panels has a low risk.
PV systems equipment like transformers and cables do not produce EMI because they have a low frequency of operation.
The only component of a solar panel system that may be capable of emitting EMI is the inverter, but they also produce very low levels of EMI (similar to electrical appliances), and the EM field is at or below background levels at a distance of 45 meters from the inverter.
Proper grounding, filtering, and circuit layout reduce potential EM radiation.
Typically the arrangement is to decommission a solar farm after 30-40 years, depending on the land leasing arrangement.
The system can be disassembled completely and the land can be restored. The site can be repurposed for other uses, such as agricultural production.
Once the solar farm is decommissioned the solar components will be repurposed or recycled including the solar panels, inverter, cabling and aluminium racking and steel posts.
New Zealand has a good amount of sunshine throughout the year, and solar power is becoming increasingly popular as a renewable energy source in Aotearoa.
While the amount of sunlight may vary depending on the location, time of day, and season, solar panels are still able to generate a significant amount of energy even on cloudy days.
Solar is widespread throughout Europe, with many countries experiencing less sun than New Zealand. For example Germany has an average solar generation potential of 1088 kWh/m2 (much lower than New Zealand). Until a few years ago, Germany was the world’s leading country for solar installed capacity. Today, Germany has over 60 GW of solar capacity installed.
There are ways the solar developers can give back to the community:
- Actively engaging with locals to help address any concerns
- Supporting local charities
- Create a viewing platform for the solar farm and create educational content for school children.
- Creating jobs for locals (please see next paragraph below).
- Working with local iwi and hapu to address concerns and work together to ensure the special cultural and spiritual relationship mana whenua have with the environment remains.
Solar farms on a large scale provide job opportunities for people in nearby communities, which is a highly beneficial outcome. In fact, the development and installation of solar panels, along with their maintenance and repair, are often labour-intensive processes that require the hard work of a skilled workforce.
It has been estimated that two Waikato solar farm projects would create up to 280 jobs.
In the initial stages of a solar power project, workers are needed to assess the location, plan the installation, this may include contracting local planners, environmental consultants and geotechnical engineers.
During the installation stage a variety of labour and technical workers are required including local electricians and construction workers. Who all must be trained and skilled in the specialised tasks necessary to build the solar farm.
Once a solar power project is operational, the ongoing maintenance and repair of solar panels provide additional opportunities for local employment.
At this early stage of the utility scale solar power industry in New Zealand there is understandably concerns that properties nearby solar power farms could lose their value mainly due to the visual element of solar farms.
Before granting solar developers resource consent the local council will assess the developers plan to mitigate visual effects they might have to neighbouring properties and the passersby. Visual mitigation is normally planting of vegetation.
The solar arrays are generally no higher than 3 meters. While planting can help eliminate most visibility of the solar panels, there may be raised vantage points where planting can not mitigate the view of the solar farm.
As more solar power comes online, there will be less need for other more visibility intrusive power plants such as wind, geothermal and hydroelectricity.
Solar farms do not create any significant health hazards. Solar panels generate electricity by converting sunlight into electrical energy, and this process does not produce any harmful emissions or byproducts that could pose a health risk.
However, like any construction project, solar farms can pose some minor health and safety risks during the installation phase. For example, workers installing the solar panels may be exposed to risks such as falls, electrical hazards (e.g. arc flash burns), or other accidents associated with construction work.
While solar panels contain heavy metals like lead and copper they will not leach into the soil therefore will not affect the local bore water.
Heavy metal found in the solar panels are typically contained within the solar panel's protective layers, including the glass, backsheet, and encapsulant, which prevent them from leaching into the environment.
Yes, solar power is becoming increasingly economically feasible. The cost of solar technology has decreased significantly over the years. In recent years solar power in New Zealand has become competitive with centralised power generation such as geothermal and fossil fuel-based electricity source.
According to the International energy agency “Utility-scale solar PV and onshore wind are the cheapest options for new electricity generation in a significant majority of countries worldwide”.
Solar power systems have low operating costs, as they require very little maintenance and have no fuel costs. Overall, the decreasing cost of solar technology and the long-term cost savings make solar power an economically feasible energy option.
Extensive research takes place to choose the perfect location for a large scale solar farm. Site selection processes include:
- Solar Radiation
Sites are analysed for the amount of solar energy that can be harnessed in the area. Factors like local weather, shading from hills and structures.
- Land Suitability
Solar farms require a significant amount of land, so sites with sufficient available space are preferred. Additionally, the land should be relatively flat and free from shading or obstructions that could reduce the amount of sunlight that reaches the solar panels.
Land will be chosen for it’s minimal environmental impact on local wildlife and cultural heritage.
Other considerations include: soil type, drainage, risk of extreme weather events like high wind and flooding.
- Grid connection
A solar farm needs to be able to distribute the power it generates, therefore it is essential to assess the local lines capacity or whether there is the ability to connect to Transpower’s transmission lines or the local Electrical Distribution Business (EBD) power lines ie Vector, Powerco etc.
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