Want to know how? We quizzed Stace Tzamtzidis, Director of Sales at solar engineering and technology company Planet Ark Power (a partner of Planet Ark), on what businesses need to know about rooftop solar.  

Q1: How much do rooftop solar systems cost?

A: There are several factors that determine the cost of a rooftop solar system, including the design of the roof and the brand and quality of the solar panels and inverter. A 100kW solar system can vary from $80,000 to $130,000 (after government rebates – see question 10 for more information) depending on site conditions and equipment used. Typically, a solar system has a payback of two to four years. Reputable solar companies will be able to provide you with an estimate of energy and cost savings upfront, as well as a solar generation guarantee.  

Q2: How big do solar systems need to be to power a whole business?

A: This will depend on how much energy is required to power the business’ operations. For example, an energy intensive business that has a factory with machinery will require far more energy than an office. 

When designing a solar PV (rooftop) solution for a commercial customer there are a number of key factors we take into account to determine how big the installation could be: 

• the energy profile of the building (how and when energy is used throughout the day, electricity tariffs)

• how the customer is billed (what component of the electricity bill comprises fixed, variable and demand charges, whether the customer is billed in kW or kVA)

• financial performance (the rate of return on investment, how to maximise government rebates and subsides, energy and cost savings)

• and, finally, available roof space on the building and the budget of the customer.

Q3: How much money can a business save by installing rooftop solar?

A: Businesses with large rooftop solar systems (around 100kW) can save thousands of dollars a year on their electricity bills. As an example of what can be achieved, Planet Ark Power installed large-scale solar systems totalling almost 500kW across two sites for Group Linen Services (GLS) in Queensland. Providing laundry services for hospitals is an energy intensive process, however, GLS is now saving 30 per cent on its energy costs and is on track to generate cost savings of close to $200,000 a year.

Q4: How does selling excess solar energy work?

A: The solar energy generated from your solar system that isn’t used can be exported into the electricity grid to be used by other businesses and households. It is up to retailers how much they will pay to purchase this energy from you, so the rate you receive will vary.

In the past commercial customers enjoyed an attractive rate for their excess energy. However, as rooftop solar uptake grows and more solar energy is exported into the electricity grid, local network operators are required to limit the amount of energy accepted in order to preserve the stability of the grid. Consequently, the income potential from selling excess solar is sharply diminished. 

There is a brand-new solution to this problem though. Planet Ark Power’s eleXsys energy management platform can be installed on-site to safely manage the export of solar energy into the grid so that it’s not capped by network operators. This enables businesses to fill their roofs with solar beyond their on-site needs and export surplus solar energy into the grid. 

Planet Ark Power recently started construction of a large-scale rooftop solar project at IKEA in Adelaide. The system will soon be paired with advanced batteries and eleXsys, which will effectively turn the store into a solar power plant!

Q5: Is it possible to calculate how much carbon a business with solar will prevent from entering the atmosphere? 

A: Yes, for every kilowatt hour (kWh) of solar your installation generates we can calculate the carbon savings. How much carbon your solar system prevents from entering the atmosphere will vary depending on its size and where your business is located (the sunnier the location, the higher the carbon savings). 

As an example of the environmental impact businesses can have, Planet Ark Power installed 320kW of solar and 300kWh of batteries at the Gold Coast Aquatic Centre. The large-scale installation not only saves the business $100,000 per annum, but also offsets 435 tonnes of carbon dioxide emissions each year. Over the lifespan of the panels, that’s the equivalent of planting 1,240 trees!

Q6: Is solar as reliable as conventional forms of energy? 

A: Solar is a very reliable source of energy and is used every day to power all kinds of businesses, schools, hospitals, homes and even farms. A number of factors can impact how much energy a system is able to generate including shading, cloud cover and dirt build up on panels. However, when a reputable solar company is contracted these factors will be taken into consideration during the early planning stages. As solar works in conjunction with the electricity grid, solar production varying during the day is not noticeable. 

Q7: How long do rooftop solar systems last? Do they have to be maintained?

A: Solar panels have a design life of 25 years while good quality inverters can last ten or more years. Rooftop solar needs very little maintenance during its lifetime. Smart monitoring solutions allow owners and operators to monitor solar performance from a smart device from anywhere in the world. 

Q8: Do systems have to be purchased outright or can they be leased? 

A: Solar PV systems can be purchased outright (Capex), under an operating lease (where you pay principal and interest), or even under a Power Purchase Agreement (where the solar system is owned and operated by a third party that sells the energy to the host at a cheaper rate than an energy retailer). 

Q9: What happens to the solar panels at their end of life?

A: Solar panels, frames and inverters can be recycled. There are a growing number of recycling facilities in Australia that extract the metal, glass and copper from these devices. While solar panel recycling is still in its infancy in Australia, the Federal Government recently listed it as a high priority in the Product Stewardship Investment Fund, which means Australia will hopefully soon have a national recycling scheme for solar panels funded by the product manufacturers.

Q10: Is financial support from the government available to businesses?

A: For solar systems under 100kW there is the small-scale technology certificate rebate, and the large-scale generation certificate rebate is available for systems larger than 100kW. Planet Ark Power primarily installs large-scale systems, and our staff can identify any other rebates that may apply in your region. We recommend you discuss the purchase of the solar system with your financial advisor to best structure the purchase agreement to suit your needs and budget.