photo by: AP Photo/Charlie Riedel, File

Wind turbines are silhouetted against the sky at sunset Dec. 17, 2021, near Ellsworth, Kansas.

As industrial-scale renewable energy projects look to find some footing in Douglas County, much has been said of their potential risks and consequences — mainly by concerned members of the public.

There have been ample opportunities for them to express those concerns as bodies like the Lawrence-Douglas County Planning Commission have worked to craft more stringent regulations for wind energy projects and review application materials for the 1,105-acre Kansas Sky Energy Center project that’s aiming to become the first industrial-scale renewable energy facility within the county’s borders. It hasn’t been rare to hear community members warning commissioners of things like ice being thrown from wind turbine blades or chemicals leaking from solar panels into groundwater during the Planning Commission’s marathon meetings on those topics.

Now, a new study conducted by staff with Lawrence-Douglas County Public Health and the University of Kansas Medical Center’s Department of Population Health seeks to illuminate exactly how likely it is — and how much — such concerns would impact residents if an industrial-scale renewable energy facility were to move in nearby. The study was initiated by the Douglas County Administrator’s Office in November 2023 and completed in February.

This past week, the Journal-World took a look at the study, which aims to respond to three questions:

• What does the available peer-reviewed literature suggest about potential adverse public health issues resulting from the use of industrial-scale wind and solar energy?

• What evidence exists that supports constituent-generated public health concerns resulting from the use of industrial-scale wind and solar energy?

• What information exists about the potential public health impact of climate change?

The study makes it clear that it’s only providing a glimpse of the research that’s available now, which can change over time. In many cases, the available research notes that further study would clarify or further verify its findings. But it also asserts that what’s out there doesn’t indicate a public health risk arising from industrial-scale renewable energy projects.

“Further, it is difficult to characterize the actual impacts to climate change Douglas County will definitively experience, and available information helps anticipate potential impacts,” the study’s conclusion reads. “This review found no information which suggests that industrial scale wind or solar energy poses risks to the public health.”

The approach

The study is based on the results of searches on PubMed, a peer-reviewed literature database, using terms germane to the primary questions, such as “industrial scale,” “wind energy,” “solar energy” and “health impacts.” The second question concerning constituent-generated public health concerns involved searches using more targeted terms derived from a list compiled by the Douglas County Administrator’s Office.

“With each identified potential health impact or factor, staff sought to describe related research findings and indicate the scale and probability of impact,” the study reads.

The study follows the example of a health impact assessment conducted by the Reno County Health Department in 2018. Reno County, much like Douglas County, has been the subject of wind development interest from Florida-based energy firm NextEra Energy Resources. The company in 2018 was aiming to install more than 80 wind turbines that would make up “Pretty Prairie Wind Energy Center” in southeast Reno County, but the project stalled when NextEra lost a lawsuit and subsequent appeal challenging citizen petitions that forced a unanimous decision from the Reno County Commission in order to approve the project’s permit.

The results of the Douglas County study are represented in a series of tables that explain a potential health impact’s scale, probability, research findings and strategies for mitigation. The scale and probability sections are broken down further into categories. 

For scale, that includes individual and public impacts, which could apply either to a small or limited number of individuals or a larger group. An “inconclusive” impact, meanwhile, might mean there’s not adequate information available, and the “not applicable” category is used to describe when an issue is related not to humans but to elements like livestock or property.

The categories for impact are more straightforward: definite, probable, speculative or no evidence.

Constituent-identified concerns

One set of five potential health impacts comes directly from people living in Douglas County who reached out to county commissioners or the county’s administrative offices to convey potential public health concerns.

Only one of them applies to solar projects: the leaching of chemicals into groundwater. The study found that this issue had an inconclusive impact with inadequate information available to properly describe its scale, paired with a speculative probability meaning an impact may be possible. The study cites a meta-analysis of studies examining disposal of solar panels in landfills, which found “non-significant amounts of lead” in groundwater and noted that exposure to carcinogens was unknown.

The county study recommends mitigation strategies like advance recycling and “glass encapsulation,” which refers to the front glass sheet of a solar panel that helps it to collect sunlight while simultaneously protecting it from hailstorms and other debris.

The other four concerns listed in this section are all related to wind projects. One of them, ice throw from rotating turbine blades, played a direct role in the 2,500-foot setback distances that planning commissioners approved as part of the county’s revised wind project regulations in late January. Some planning commissioners cited evidence that turbine blades can throw ice as far as 1,700 feet away from a tower structure.

But the study finds that this concern has an inconclusive scale and speculative probability of impact. It does note that while no studies identified the extent to which ice throws or falls have resulted in injury to humans or livestock, several studies acknowledged that such incidents could result in injury and are a risk which should be considered.

Two other concerns — injuries from lightning strikes and the impact of “shadow flicker” on neurodivergent individuals — again carried an inconclusive scale of impact, but in both cases didn’t present any evidence of their probability of impact.

For lightning strikes, the study notes that no studies identified the risk to humans when lightning strikes turbine blades, though several studies exist examining the risk of damage to turbines. Additionally, “considerable research” exists that describes efforts to reduce the impact of lightning strikes on wind turbines.

“Shadow flicker,” meanwhile, refers to the effect of the sun shining through the rotating blades of a wind turbine, casting a moving shadow. The study notes that existing research has examined potential impacts for people with epilepsy, finding that shadow flicker speeds are lower than the known threshold for triggering epileptic seizures, but no studies noted any focus or concerns for people who are neurodivergent.

The last concern from this section was a wind project’s effects on livestock, including spontaneous miscarriage and birth deformities. The study found that there are “exceedingly few” cases documented in peer-reviewed literature.

On the whole, the study states that its review didn’t yield any findings based on constituent-identified concerns that suggest a public health risk.

Wind impacts

One table in the study lists a number of impacts related to wind projects: annoyance, infrasound, sleep disturbance, shadow flicker, quality of life and air pollution.

The study found that annoyance with a wind energy project had a definite impact, but usually on an individual level, based on factors like negative views and attitudes regarding wind energy. It’s also a contributor to some of the other impacts in the table, like sleep disturbance and shadow flicker.

The study found that existing research concerning sleep disturbance consists largely of small studies that often rely on self-reported sleep behavior. The same goes for quality of life impacts, and the study cites “robust” research that used a standardized tool for measuring quality of life which found no associations in perceived quality of life among 1,200 people living at varying distances from wind turbines.

Peer-reviewed research acknowledges that wind turbines produce infrasound — sound below the level of human hearing — that can be effectively minimized with properly maintained distance from residences. The study notes that the World Health Organization recommends a maximum noise level of 45 decibels from wind farms to residential areas. According to the Centers for Disease Control and Prevention, 40 decibels is roughly the same level of noise as a refrigerator hum, and 60 decibels is about the level of a normal conversation or a running air conditioner.

The table also lists one more impact: “Wind Turbine Syndrome,” a purported medical condition that includes symptoms like vertigo, nausea, fatigue, migraines and sleep deprivation. However, it clarifies that peer-reviewed literature does not recognize the syndrome and notes that several other factors may influence perceptions of self-reported symptoms.

A summary of this section of the study notes that the likelihood of negative public health impacts due to industrial-scale wind energy seems limited.

“Across studies, the more likely impact of industrial scale wind energy is an increase in annoyance, particularly among people whose (personal) attitudes and views about wind energy or the presence of industrial scale wind energy are negative,” the study reads.

Solar impacts

The final table included in the study lists five potential impacts from solar energy projects: exposure to hazardous chemicals, gentrification, exposure to electromagnetic fields, soil-related exposures and illness, and exposure to chemicals in fires.

The first item on the list, the study notes, is specific to industry workers. Existing research has found that while materials used in the construction of solar panels can include toxic or hazardous chemicals, the implications were noted exclusively for “industry and occupational settings,” not community settings. The same was true of soil-related exposures and illness.

The study classifies the other two exposure types as only being speculative in terms of their probability of impact. Concerning electromagnetic fields, existing research noted that exposure from solar farms is likely similar to devices like cell phones which are “omnipresent in everyday life.” And other research notes that fires at solar farms are a “low probability event,” although some studies document the possibility that human exposure to hazardous chemicals is possible through fires.

Research about gentrification, meanwhile, has found that utilization of land and availability of solar power may increase demand — and the price — of land, which the study notes would be expected to have a greater impact on vulnerable populations and could exacerbate inequities experience by historically marginalized populations.

Like the wind section, the study found that the likelihood of negative public health impacts due to industrial solar energy seems limited.

“Evidence suggests there are potential impacts to health for small numbers of individuals, much of which can be minimized through appropriate mitigation strategies,” the study reads.