Evaluating Solar Lighting FOR OUTDOOR AREA AND STREET APPLICATIONS

TA B L E O F C O N T E N T S Why Choose Solar?..............................................................2 How Solar Works...................................................................3 Where Does Solar Work Best?.........................................5 Site Considerations...............................................................6 Solar Lighting System Components............................. 7 System Options.....................................................................8 Installation................................................................................9 Solar Myths........................................................................... 10 Solar Lighting Savings........................................................11 What to Look for in a Solar Lighting System........... 13 What to Look for in a Solar Lighting Supplier..........14

Why Choose Solar? Solar outdoor lighting provides reliable illumination and cost-effective performance for many outdoor lighting applications including pathways, trails, sites, parking lots, and perimeter security. Solar outdoor lighting is an excellent alternative to grid-connected systems in traditional lighting applications. For projects in remote locations that are far from the grid or where it is difficult or costly to trench, solar lighting is a proven solution. Solar lighting systems are ideal for: • New construction • Remote areas • Existing locations where underground utilities are failing • Locations where electricity costs are high • Eco-sensitive landscapes • Temporary or emergency installations

Solar Advantages • No trenching, digging or cabling required • Ease of installation - can often be done by a General Contractor • Eliminates ongoing electrical costs • Meets mandates requiring backup security lighting that functions independently from the grid • Reduces maintenance cycle • Replaceable and recyclable batteries with long life span • Qualifies for LEED point-earnings for sustainable sites and energy and atmosphere credit

2

HOW SOLAR WORKS 1

S O L A R P A N E L – T H E P O W E R G E N E R AT O R The photovoltaic (PV) solar panel, or module, collects and converts the sun’s energy into electricity. The PV panel is made up of individual silicon cells. When sunlight strikes the cells, it causes the electrons to move, creating a DC current flowing within each cell. Different sizes (wattages) of solar panels are available and are carefully chosen based on site location, application, customer lighting requirements, and the amount of solar insolation (light) available. Solar panels are durable and able to deliver reliable power even in extreme weather conditions.

2

ENERGY MANAGEMENT SYSTEM An efficient and reliable solar lighting system requires a controller to manage and optimize the energy flow. The controller monitors the voltage, temperature, and battery state-of-charge to ensure the battery is charging and discharging properly. Sophisticated systems use Energy Management Systems, which are capable of managing dimming, when acceptable, for increased energy savings. They may also feature an LED driver to operate and regulate light output of the LEDs.

3

B AT T E R Y – T H E P O W E R S T O R A G E The electrical energy generated by the solar panel and managed by the controller is then stored in the batteries. This power is drawn to operate the LED luminaire from dusk to dawn. The size and amount of battery storage needed is dependent upon customer specified operating requirements and light intensities. It is important that sufficient battery storage is provided to operate each night and supply backup power in case of tough weather conditions (generally 3-5 nights). This is referred to as the “autonomy” of the system, which considers latitude and available sunlight at the project location along with system efficiencies and design.

3

1

I N F R O M S O L A R PA N E L

2 CONTROLLER

O U T TO L I G H T I N TO B AT T E R Y

3

O U T F R O M B AT T E R Y

4 3

Where Does Solar Work Best? Generally, as long as there is sunlight, a solar panel will generate some amount of power. However, the latitude of an installation site determines how much solar energy a system can collect, and the viability of a solar-powered solution depends on your application requirements. Locations that have longer sun hours per day or are closer to the equator have greater solar insolation and are ideal for solar technology use. In locations with lower insolation, solar lighting can still be a viable solution based on proper system design. Additional solar panel area, increased battery storage, and an efficient energy management system can offset lower insolation values and provide reliable illumination for your lighting application. The solar insolation map below shows the average solar collection per day across the USA, based on the insolation values for the worst month of the year for a given location. Solar lighting manufacturers can help determine your location’s solar insolation value to help choose the correct lighting system. kWh/m2/Day

< 3.0

3.0-3.5

3.5-4.0

4.0-4.5

4.5-5.0

5.0-5.5

5.5-6.0

Credit: National Renewable Energy Laboratory, for the U.S. Department of Energy. Billy J. Roberts. 19 September, 2012.

4 5

6.0-6.5

> 6.5

Site Considerations Before a solar lighting supplier can provide an efficient and costeffective lighting system, the architect, designer, or project manager needs to determine several site factors:

Soil Conditions Rocky soil conditions are a significant problem for grid-tied lighting because of high trenching costs. For tough soil conditions, solar is an attractive and costeffective choice as trenching and cabling is not required.

Climate and Environmental Factors Even in extreme heat and cold climates, solar is a viable solution for outdoor lighting when systems use components designed for tough environments. In latitudes that receive snow, panels are normally angled at 45-60 degrees for maximum solar collection. This prevents snow build-up from inhibiting energy generation. Solar outdoor lighting systems are also designed to withstand high winds, hail, humidity, and salt.

Shading Shading can significantly lower the collection and power generation capabilities of a PV system. If a solar panel is in full shade, it will not operate. It is important to be aware of the site-specific shade effects to determine the placement of solar lighting systems for optimal operation. In locations where there is high shade, solar may not be a viable solution.

6 5

Solar Lighting System Components Solar Panel High-efficiency PV module to collect and convert energy from the sun.

Energy Storage (Batteries) Collected energy is stored to power LED luminaire when light is needed.

Energy Management System Sophisticated lighting systems will regulate the flow of energy to protect the batteries from over or under charging and regulate light output levels in one integrated system.

Luminaire Superior LED lighting technology and fixtures.

6 7

Support Structure Supports PV panel and system engine.

System Options Solar outdoor lighting systems feature a number of the same options as grid-tied systems. The most popular include dimming, decorative poles and fixtures, and multi-fixture design. Dimming Dimming options enable energy reduction by maintaining lower light levels when acceptable: for instance, the system could lower light levels between two and six a.m. when there is less demand. Dimming can save money, as energy savings allow for a reduced system size.

Decorative Poles and Fixtures Some lighting applications require the use of decorative poles or fixtures to match a neighborhood theme. Solar lighting systems can be installed on most pole designs. Additionally, many decorative LED fixtures can be adapted to work with solar-powered systems.

Two Fixtures on a Pole In some lighting designs, two fixtures are required to be mounted on the same pole. This option is possible with solar-powered systems as well. However, increased lighting levels need to be accounted for when sizing a solar system to ensure adequate energy collection and storage capacity.

Regulatory Compliance and Certifications Many solar outdoor lighting systems are designed to meet IES lighting level and design standards, local and international building code (IBE) standards, AASHTO standards, and zoning bylaws. Some system options also meet UL certification requirements.

8 7

I N S TA L L AT I O N When considering a new lighting installation, solar lighting systems are easier, faster, and less costly compared to grid-tied installations. If retrofitting grid-tied lights with solar-powered systems, existing poles and bases need to be replaced, in most cases. This is because grid-tied poles are not sized for the additional wind load that solar energy systems can generate.

NO TRENCHING OR WIRING REQUIRED

QUICK & EASY I N S TA L L AT I O N

Saves time and cost.

Installs in days instead of weeks.

NO SPECIAL EQUIPMENT REQUIRED

USE EXISTING WORK CREWS

Systems can be installed with few special tools or equipment. In some cases a bucket truck may be required.

Many solar lighting systems are pre-configured to connect together and do not require an electrician or approved contractor to install. Often, a general contractor or facility and maintenance crew can complete the installation.

*In most cases, permits and inspections may be required. Installers should check with the organization that has jurisdiction of the installation.

9

Solar Myths Myth: “Solar lights are too expensive.” FACT: The cost of solar technology has fallen significantly over the last few years, making solar power a viable energy alternative.

Myth: “Solar lights do not last all night long.” FACT: Improved solar illumination technology is reliable and, with adequate battery storage, will work through the night. Sophisticated solar lighting systems should provide three to five days of autonomy.

Myth: “Solar is always more expensive than electricity.” FACT: When the cost of electrical infrastructure, trenching, and wiring are considered, off-grid solar lighting is a cost-effective alternative to on-grid lighting, especially in locations where trenching is difficult or infeasible.

10 9

SOLAR LIGHTING

In many cases, the total cost of ownership for solar lighting over the life of the system is more affordable than grid-tied lighting. When you choose a solar lighting system, you save on costs in the following areas: 

NO TRENCHING

NO WIRING

Eliminates the cost of digging trenches for underground wiring.

Eliminates the cost of installing underground wire, a distribution panel, and a control panel.

R E D U C E D I N S TA L L AT I O N C O S T S A N D T I M E S AV I N G S

NO LAND USAGE ISSUES

Many solar lighting systems are quick to install due to pre-configured wiring. In most cases, a general contractor can install a system with only a bucket truck. 11

With solar lighting, there is no need to negotiate with property owners for underground access.

NO REPLACEMENT LANDSCAPING

NO ELECTRIC USAGE AND DEMAND CHARGES

Save on the cost of replacing and repairing ground that is torn up during the trenching process for grid-tied lighting.

Eliminates electrical usage and electric bills.

NO ELECTRIC METER There is no need for an electric meter, saving costs of meter installation and grid connection fees.

REDUCED MAINTENANCE Systems feature replaceable and recyclable batteries with long life spans, keeping maintenance requirements and costs low. 12

What to Look for in a Solar Lighting System Solar lighting systems should include several key features and high-quality components in order to provide an efficient and reliable solution.

Look for the following in a solar lighting system:

13

•

Integrated top-of-pole, theft-resistant design

•

Designed to withstand -13°F to +130°F (-25°C to +55°C)

•

High-performance LED luminaire

•

Electrical components sealed from dust and moisture

•

Solar engine that flips open for easy maintenance

•

Versatile battery enclosure to securely house 1-4 batteries

•

All metals hot-dipped galvanized or stainless steel

•

Salt and UV corrosion-resistant

•

Designed to withstand up to 150 mph (240 km) wind load

•

Component lifespan in years •

Solar panels: 20+

•

Batteries: 5

•

EMS: 10

•

LED fixture: 10

What to Look for in a Solar Lighting Supplier While the components of a solar lighting system may seem complex, a professional solutions provider will ensure all the pieces come together seamlessly.

There are a number of services a qualified supplier should offer: •

Digital photometric studies to show accurate light levels

•

System drawings and specifications

•

Pole sizing information

•

Simulating tools specific to solar lighting

A supplier’s simulating tools should provide installers with maximum light output, maximum autonomy, and maximum reliability at a specific location and be based on how the system will be used. Using this information, a professional supplier will design a system by integrating quality components that are configured per installation requirements and application to produce the most efficient, long-lasting, and cost-effective lighting solution.

14

by carmanah® To learn more about our solar outdoor lighting solutions, please contact us: Phone: 1.800.959.1329 Direct: 1.772.286.9461 Email: [email protected] Website: solarlighting.com