How To Design A Successful Outdoor Solar Lighting Installation

In this post we’re aiming to assist professional lighting and project and assets managers in the successful design, procurement, and installation of outdoor solar lighting, regardless of whether it be path, street, park, carpark, marina, or jetty solar lighting.

About Solar Lighting

Over the last couple of decades we have seen huge advances in solar powered technology, and one of the major beneficiaries is outdoor lighting. Today, outdoor solar lighting is available in all sizes and shapes and is no longer only used in private homes and gardens. Commercial solar lighting systems have benefited too, and now outdoor solar lights not only meet every requirement, they also deliver huge benefits.

Solar lighting has become a proven commercially viable and reliable solution for numerous lighting applications and has very quickly become mainstream technology for discerning councils, mining companies, government departments, and many other businesses. There’s now a wide range of solar lighting options available, all of which can be tailored to suit different aesthetical and functional preferences.

Outdoor lighting serves a number of practical purposes and benefits for both residential and commercial properties. It can create the perfect ambience at a hosted event, add style to and compliment any building, and ward off potential and real threats. Whether the reason is safety, functionality, or design, there are many reasons why solar powered outdoor lighting is an effective and affordable lighting solution.

Businesses can choose from –

• Solar flood lights,

• Solar lanterns,

• Solar spotlights,

• Solar powered lamp posts,

• Solar powered motion lights,

• Solar streetlights,

• Solar pathway lighting, and

• Decorative and ambient solar lights.

The advantages of solar lighting include –

• It’s environmentally friendly,

• It’s cost effective,

• The source is unlimited,

• Solar lighting systems require little maintenance, and

• It’s available in a wide range of styles.

When choosing solar lights, the following factors must be assessed. These factors are often inadvertently overlooked; however, being aware of these considerations prior to purchasing solar lights can help avoid potential system failure, servicing costs, and even expensive replacements.

Check Out The Manufacturer and/or Supplier

Do your own research to discover how long the solar lighting manufacturer and/or supplier has been in the solar lighting business and determine if they have the required experience, as well as a good business track record. Is solar lighting a side-line for them or is it their core business? Can they provide references for jobs completed? We strongly suggest you go out and inspect these completed installations at night-time.

Check the Quality of Components

Again, it’s up to you to do your own research and ask the right questions. You need to ensure all components have the right credentials and have been part of the solar lighting market long enough to have proven themselves. Are spare parts readily available? What warranties will you receive?

How To Achieve a Top-Quality Solar Lighting Outcome

For compliant and mission critical solar lighting, and to ensure that optimum optic is used, a professional lighting design should be undertaken using the least number of lights, all the while ensuring the light is safe and compliant, and fulfills the following conditions –

• No glare to the user.

• Warm white and natural colour temperatures are typically most desirable (between 4500k and 2700K). Recent research revealed that blue white and cool colour temperatures are harmful to both humans and animals; our natural circadian rhythms are affected unless the blue is removed from the light.

• No light pollution up light or into neighbouring properties.

• Dark sky compliant.

Appropriately Sized Solar Panelling and Battery

One of the biggest problems we hear about is manufacturers and/or suppliers not fully understanding system sizing, and they supply a solar panel and/or battery that’s simply not big enough. The result is inconvenience and additional costs to the end consumer as it causes unreliable light, with the battery life plummeting due to being exposed to frequent deep discharges.

Because batteries are the largest and most expensive consumable, it’s very important to get the battery size right: a good quality and appropriately sized battery, when used in conjunction with a correctly sized solar panel, should last anywhere between 5 and 10 years.

The general rule of thumb for most of mainland Australia is that a solar lighting system must supply four full nights of battery back-up; this is to allow for the longest winter nights. In Melbourne, for example, this figure is 14.39 hours. That means the light should be powered by the battery at 100% illumination for a period of 56.56 hours, without any input from the solar panel.

We give this example only to indicate battery back-up requirements. In the monsoon season in tropical cities like Cairns or Darwin for example, 5 nights of batter back-up are required, but of course in the summer the nights are much shorter.

In calculating battery back-up, know that a lead acid battery can’t discharge more than 70%, while the average daily depth of discharge must not surpass 50%. Lithium batteries can’t discharge more than 80%.

When calculating the size of battery required, de-rating must be also considered, which allows for degradation over time, performance drop in extreme temperatures, dirt on the solar panel, and voltage drop.

As per the AS/NZS 4509.2 Stand-alone power systems – system design guidelines, a minimum of 30% extra solar panel should be allowed for these additional factors.

Compliance

This section only applies to larger solar street
lighting systems.

These systems must comply with all applicable Australian standards including the standard relating to the design of standalone power systems (AS/NZS 4509.2), standards relating to the signage of battery enclosures (AS/NZS 4509.1), and standards relating to electrical safety (AS/NZS 3000). In addition, RCM compliance of all light fixtures must be ensured.

By following these compliance points, product safety and life will be maximised, and maintenance minimised, leading to savings in the long term.

Read more about Planning solar lighting? Ignore this at your peril