Codes + Standards, Craig’s Lighting Articles, Interviews + Opinion

DLC’s Andrew Antares Talks Light Pollution Mitigation

I recently had the opportunity to interview Andrew Antares, Project Manager of Technical Development, DesignLights Consortium (DLC), for an article I developed for the November 2023 issue of Electrical Contractor Magazine, the official NECA publication. The topic: new sample language that municipalities can use to address “light pollution” as a potential byproduct of outdoor lighting.

DiLouie: Light pollution is a longstanding umbrella issue in outdoor lighting that has been addressed using various ordinances, rating systems, and product features. How significant an issue is it today, and what is the cost of this?

Antares: The light pollution problem is bad and it’s getting worse. Outdoor lighting proliferation has resulted in the unintended consequence of light pollution. That’s not to say that we shouldn’t continue to pursue high performance lighting and lower costs, but we should do so while mitigating the negative consequences of light pollution.

The night skies are getting brighter year over year.  We are learning that light pollution is increasing at a much faster pace than previously thought  – about 10% every year.

And it’s not just that we can’t see a sky full of stars at night. Light trespass, which is wasted light shining in unneeded areas, is also a form of light pollution that should be alleviated.  Furthermore, light pollution is causing negative ecological impacts to a wide range of insects, plants and animals. For example:

  • It is estimated that up to one million species, including up to 40% of insects, will become extinct in the next few decades. Insects are a key part of the food web and light pollution interferes with insect development, movement, foraging, reproduction, and exacerbates predation, and as a result is a significant factor in insect declines.
  • Light pollution interferes with bird and bat migration. Billions of birds migrate in the middle of the night while we sleep. Light from cities attracts birds from their migratory paths and once in the cities can disorient them. Birds may collide with illuminated glazing and young birds have been observed to circle around lights until they fall out of the sky from exhaustion. Light pollution from cities also interferes with migrating bats looking for dark stopover points.
  • Light pollution disorients sea turtles from entering the surf when they hatch and they orient instead towards the light source. In Hawaii, for example, turtles were observed orienting towards an inland park, drawn to an unshielded bathroom light source. Instead of reaching the surf, they succumbed to exhaustion or were eaten by predators.

DiLouie: Light pollution is often addressed at the local jurisdiction level via bylaws and ordinances. The DLC recently published sample language addressing light pollution mitigation for these. Why did the DLC take this step? What problems does this solve?

Antares: With LUNA, we are focusing on helping local governments meet their light pollution concerns and energy efficiency goals in an easy, prescriptive way. We are providing a Qualified Products List (QPL) with LUNA qualified products that are energy efficient, dimmable and controllable, and have warm white color temperature. By providing them with a sample ordinance or bylaw language that assures that all of the necessary attributes of lighting that are needed to meet light pollution and energy efficiency goals are addressed. The ordinances in place today vary widely, and comprehensive ordinances that address light color, uplight or light trespass, and controllability are few and far between. Local governments design laws that focus on the end result and the experience of their residents, but do not necessarily include performance specifications of the products. Of course, this makes sense, because local planners and zoning officials aren’t lighting engineers!

The sample ordinance is essentially the LUNA technical requirements but phrased and formatted for municipalities. The sample ordinance offers two approaches. The simple approach is for municipalities to say, “Hey, you can only get light fixtures for this project from the LUNA Qualified Products List (QPL).” This means they don’t have to review any additional performance requirements beyond those already in place. But, if they don’t feel comfortable doing that, the sample language also provides a second approach that spells out the performance requirements so municipalities can review products themselves.

The end goal is to uniformly address performance requirements so that manufacturers can more easily meet the regulations for energy efficient night sky friendly lighting. Ideally, this will mean more communities will adopt comprehensive light pollution measures if they know that all their energy efficiency, quality, and light pollution concerns can be addressed prescriptively with the LUNA QPL. In turn, this will mean that more products will want to be LUNA qualified. Municipalities that adopt LUNA early may create an impact that will extend far beyond their jurisdictions.

DiLouie: Did you conduct a review of existing bylaws and ordinances? What were your major findings from this review?

Antares: Yes, and we made an ordinance map to help our stakeholders easily find these regulations. This involved creating criteria for inclusion in our light pollution ordinance map, finding local ordinances in code databases, and then comparing them against these criteria. We are tracking ordinances on an ongoing basis, but we do have a few takeaways so far:

  • Different dark sky ordinances have different goals in mind. About half focus on restricting light trespass, with restrictions on the light level at the property boundary. Others are more focused on light pollution and its impact on wildlife, with restrictions on color temperature, uplight, and more.
  • The most common performance requirement is for “shielded” fixtures or the use of “full-cutoff” fixtures. The problem here is that there is no standard definition of a “shielded fixture” and the term “full-cutoff” has been deprecated and replaced with the Illuminating Engineering Society (IES) Backlight-Uplight-Glare (BUG) Ratings.
  • Less than a quarter of the ordinances had a maximum color temperature requirement, and almost none had a dimming requirement. However, a larger portion of them did require sensors or have timing requirements for when luminaires are allowed to be on and off.
  • Overall, most of the ordinances are still pretty human-centric and there is a lot of room to make things better for other organisms with interventions such as seasonal dimming/switching requirements and prescribing the use of non-white outdoor lighting for environmentally sensitive areas.
  • Using industry standard metrics like color temperature and Backlight-Uplight-Glare (BUG) Ratings would help make many of the ordinances more comprehensive and more objective, as it wasn’t uncommon for them to use vague and deprecated language.

DiLouie: In 2011, the Illuminating Engineering Society and the IDA introduced the Model Lighting Ordinance to provide actionable sample language. What does the DLC sample language accomplish either in tandem or as an alternative to the MLO?

Antares: The MLO and the DLC sample ordinance language are similar in that they support similar goals, but they differ in their performance requirements. LUNA requirements are not linked to lighting zones nor application criteria like those in the MLO. LUNA provides prescriptive thresholds for light fixtures, vs. prescriptive or performance thresholds for the site as the MLO does. The Illuminating Engineering Society (IES) BUG rating system is used in both documents, but there are differences in the maximum values allowed. In general, LUNA has more stringent U (Uplight) Rating requirements than the MLO, but has no threshold requirements for B (Backlight) or G (Glare) Ratings. Every LUNA and DLC listed outdoor light fixture reports all three BUG ratings so you can review those to see if you comply with the MLO thresholds.

LUNA goes beyond the MLO with maximum and minimum color temperature requirements, and every product has to be dimmable down to at least 20% of full power. There are other prescriptive differences too: every pole- or arm-mounted LUNA qualified light fixture has to have a shield available for order and the mounting mechanism cannot tilt more than 10 degrees. If you have a fixture with no uplight but you tilt it 30 degrees to light your parking lot, you have not minimized light pollution, but instead have made it worse.

DiLouie: Do you see any opportunities for large commercial real estate property firms or corporations with a substantial brick-and-mortar presence to adopt the sample language as a design policy for their properties?

Antares: Yes! Commercial properties with a large parking footprint may create a lot of light pollution, which is a big part of the reason why we’re seeing communities becoming interested in adopting light pollution ordinances. The rural town with 5,000 residents is going to see a big difference in their night sky when a big box store comes in and installs 100 lights in their parking lot.

Commercial businesses of all sizes need to be good neighbors, too. Nobody wants to have to shield their eyes from glare while they’re driving at night, and they don’t need to see the glow on the horizon to know where the mall is. Firms that adopt the DLC sample ordinance language in their design policies would be prioritizing outdoor lighting that is controllable, energy efficient, and night sky friendly. Outdoor LED fixtures are meant to last for a decade or more, so adopting the LUNA performance requirements would be a simple measure to ensure long lasting light pollution mitigation.

DiLouie: What is the argument here? If you stood in front of a town council or commercial property representative, what in-a-nutshell case would you make to convince them to take measures to address light pollution?

Antares: These stakeholders are concerned with asset management and energy use and value dimming and scheduling capability. LUNA’s controllability requirements set a minimum dimming threshold of at least 20%, but they also set reporting requirements for control protocols.

Preserving our connection to the night sky is something that many people see as important, especially in rural areas, but in more densely populated areas the more immediate impact of light pollution is often light trespass. People don’t want light from a nearby light fixture shining in their window at night, and LUNA-listed products have at least one shielding option to potentially mitigate a light trespass complaint.

DiLouie: Mitigating light pollution simply makes sense, but it is not always addressed through best practice. Where do you see the biggest hurdle? Is it primarily in product availability, lack of awareness among end-users, insufficient perceived benefit for the cost, poorly written bylaws, or something else?

Antares: We have heard that there are two major hurdles. The first hurdle we hear about  is a lack of awareness on the importance of light pollution mitigation from lighting specifiers (including contractors on small projects) driving the specification for low color temperature, night sky friendly light fixtures. In many situations, energy savings from LED retrofits trumps all other considerations. It is clear that the most important crisis we face is climate change, and energy efficiency is an important consideration in our efforts to decarbonize our built environment. But we should not do so without thinking about the impacts of light pollution, including light trespass, on people and other organisms that share this planet. Every retrofit that ignores light pollution mitigation is a long-term loss Since LUNA addresses color temperature, uplight and controllability at the light fixture level, communities adopting LUNA products can focus on application concerns like over lighting and light trespass to address human and ecological impacts.

The second hurdle is education for local governments. Ordinances and bylaws are rarely comprehensive, and often proliferate by being copied from other communities. The DLC has created resources for local governments to help them easily understand the big picture problems and provide them with solutions to address these problems. The LUNA program is designed to help the market find outdoor lighting that is both energy efficient and night sky friendly, and our performance requirements are intended to address those green goals from a pragmatic standpoint.

DiLouie: In April 2022, the DLC launched the LUNA qualifications for outdoor lighting products as a subset of the outdoor lighting category in its SSL Qualified Products List. How many products have registered, and what have you learned so far?

Antares: We have 65 products listed so far and many more under review. LUNA listed products are eligible for incentives because they also meet our SSL QPL V5.1, but there aren’t necessarily additional incremental incentives. We have learned that incentives are not driving adoption of energy efficient night sky friendly lighting, because end users are not aware that they should be prioritizing outdoor lighting that is both energy efficient and mitigates light pollution. So, we are working to provide easy-to-understand and easy-to-implement resources and at the same time we are learning what is needed to drive additional change.

DiLouie: If the entire country adopted this sample language and installed LUNA products, would our towns and cities look like at night?

Antares: We’re all guilty of the misconception that more light equals more safety. But the truth is that more light beyond what is needed provides no value and leads to unwanted energy costs and more light pollution. Lighting at night benefits people; for most other organisms it is a detriment. So if there aren’t people present, we don’t need to light empty parking lots and parks – this is where the use of occupancy sensors comes in.

If there was greater adoption of LUNA, then we would provide the right amount of light at the right time, without wasting energy. We could stop, and eventually reverse, the year over year increase in light pollution that has been occurring. But, the LUNA program doesn’t yet provide solutions for environmentally sensitive applications where non-white “amber” and red outdoor lighting is needed. One of the main reasons we don’t cover these fixture types is because there is a lack of standards for these LED sources. We have published a framework for standards bodies to consider and are supporting their efforts to create standards for these LED sources so we can potentially include them in LUNA in the future.

DiLouie: What is the role for electrical contractors here? What are the opportunities for ECs to act as ambassadors, consultants, installers, and retrofitters?

Antares: Communities and business owners rely on ECs to be the experts. You’ve got to be a catalogue, a designer, and these days a programmer. You’ve got to navigate the red tape in both governments and utilities, and you’ve got to deliver a project that somehow makes everyone happy. It’s an incredibly complicated role!

For outdoor lighting products, the LUNA QPL gives you an easy button. You have a growing list to choose from and you know that anything on the QPL is going to check important boxes like incentive money eligibility, low color temperature, minimal uplight, shielding options, and controllability.

DiLouie: If you could tell the entire electrical industry just one thing about light pollution and the DLC’s sample language, what would it be?

Antares: The goal with LUNA is to make it easy to find energy efficiency and night sky friendly light so ECs can be the heroes that help their clients meet both their operational and environmental goals.

If you’re working off the LUNA QPL, then you’ll be working with products that have those attributes and control capabilities from the onset and that these products can help.

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Craig DiLouie


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