You’d think it would be pretty easy to sell solar systems to homeowners. “Here’s a proven technology that sits on your roof and cuts your reliance on your polluting energy provider,” says the doorknocker. “OK, that’s great,” says the door-opener. “How much does it cost and how much money will it save me?”

All of a sudden things are a lot more complex, because people use electricity at different times and in different ways. One family might get by with a small PV system whereas the neighbour’s load might be so high it could be mistaken for a suburban aluminium smelter.

Finn Peacock, the founder and CEO of SolarQuotes, a go-between that links buyers with a range of PV installers, has seen thousands of customers’ reactions to the impact of solar on energy bills and says almost all of them get one simple thing wrong: they calculate payback by annualising the most recent electricity bill.

That will give you a very wonky estimate of payback period, or course, because it will not account for the seasonal variation in generation and usage – which can be dramatic.

Peacock’s solution is a payback period calculator that offers a far better reflection of real life. “It’s all about transparency and letting people play around with it instead of giving them one big assumption that may or may not be right,” he tells EcoGeneration.

Finn Peacock can match you up with some prospective residential PV and storage customers, if you haven’t spoken to him yet.

How it works

Curious users get to plug in their postcode, the system size they’re considering, roof orientation and angle, whether or not they want a battery, system cost, current retailer’s charge per kWh, an estimate of annual payment to your current retailer and the feed-in tariff paid for exported solar. Click a button and up pops an estimate of payback period in years along with savings for the first year and the next four quarterly bills.

The tool is another offering in SolarQuotes’ mission to serve two sides of the solar market: consumers and installers. For consumers, the goal is to make the purchase of high-quality solar easy, low-risk and fun. “Promoting the quality side of solar is what we do for the consumer,” Peacock says. “We shout it from the rooftops: SolarQuotes is not the place to buy the cheapest system. It breaks my heart to see solar go on a roof and get pulled off three years later and go into landfill. It’s all too common. They should be lasting 30 years.”

The go-between

The other mission is to help good solar installers thrive, he says, by taking care of marketing for them and making their sales as easy as possible. SolarQuotes will source three quotes from its network of trusted installers, leaving the final decision to the buyer. Nearly half a million people have used SolarQuotes since 2009, which is one in 20 homes. “We’re always growing; we’re busier than we’ve ever been.”

Peacock is pretty complimentary about the standard of work from installer-owned installation firms. There is a small number of unscrupulous ones, he says, and there probably always will be, but they don’t last long because “their reputation catches up with them on the internet”.

The poor work in the world of rooftop PV can often be attributed to large organisations that subcontract out at too low a price, where even good installers are incentivised to get a job done very quickly. “Sometimes they’re bad installers but often they’re good installers that are just rushed,” he says. “You can do high-volume, low-margin solar well, but it is very hard.”

Reputation counts

Generally, the big sales companies are out to make as much money as possible in as short a time as possible. A hardened economic rationalist would blame the presence of subsidies, but Peacock says it’s not that black and white. The net effect of Small-scale Technology Certificates, he says, is “overwhelmingly brilliant”. The solar installation market in Australia would be nowhere near as buoyant without the boost it received from subsidies provided through the federal government’s Renewable Energy Target. “That’s why one-in-five houses have solar and a big reason why we pay a fraction of the price the Americans do,” he says.

But whenever free money is available the marketing message can be easily distorted, and customers will be lured by discounts. That might distract them from making an effort to understand and research what they are buying. “Most consumers get it when you have the ‘quality’ conversation, they really do.”

If rebates are very generous, as they are in some states, then small premiums for better equipment look proportionally larger than if subsidies were slimmer. It’s starting to happen in South Australia, he says, where a Tesla Powerwall 2 that should cost between $15,000 and $16,000 installed can be had for about $3,500, thanks to a state rebate for storage and a kickback should the owner connect with a virtual power plant. “I am very worried about the quality of battery installs in South Australia right now,” Peacock says. “I’m worried that corners may be cut on the installs.”

Feedback on the phones

When EcoGeneration fiddled about with the calculator we found the inclusion of storage from a menu of battery options pushed payback periods way out, indicating the technology still expensive. But don’t take our word for it – your correspondent gets by on 2.5kWh a day.

The calculator relies on various inputs to model usage and generation, including local solar irradiance data as measured by the National Renewable Energy Laboratory in the US to calculate sunlight hitting panels, solar self-consumption and how much solar energy would be exported to the grid or put into a battery. “This allows us to calculate the predicted bill for each season,” Peacock says. Solar monitoring company Solar Analytics provided seasonal electricity usage patterns for each state and territory in Australia.

Peacock, a chartered electrical engineer who previously worked at the CSIRO’s Energy Transformed Flagship, says SolarQuotes often takes calls from consumers asking for an opinion on the $2,600 6kW system they’re about to purchase, to be told quite frankly that they should think long and hard about the quality and long-term prospects of such a cheap PV system. Most callers will listen and some might change their minds. A small number get grumpy and assume it’s all a ruse designed to rip them off.

That’s the way it is when you try to do someone a favour sometimes.