The northern side of a roof is the most common place for solar panels to be mounted in Australia, as that side gets the most sunlight over the course of a sunny day.

But while the panels might get the most light, it doesn't necessarily come at the right time for all families, ShineHub solar consultant Alex Georgiou told ABC Radio Adelaide.

Mr Georgiou is working with South Australian charities, including the National Trust SA, SA Conservation Council and the Australian Solar Council, to help them get better returns for their solar systems.

Although current systems are aligned to get the best energy input during the day, with dropping rebate rates for electricity sent back to the grid, Mr Georgiou suggested it was time for many people to rethink their set-ups.

He told ABC Radio Adelaide the smartest financial choice was once to feed the power back in, but now it might be better to produce power when you need it most.

"Instead of wanting to get this high feed-in tariff credit, [now] you want to use all of the power in your house," he said.

Mr Georgiou said the traditional solar panel mounting on the northern side ensured most of the power was produced in the middle of the day — when we are not home to use it.

Asking installers to split panel arrays may work better for you. ( Supplied: Mike Roberts )

"If you are working and not home, all you are doing is buying solar and giving all that power back to the grid," Mr Georgiou said.

"The bills don't go down and [people] think '[solar] doesn't work'."

Splitting your system could provide the best return

Mr Georgiou said you can get the best panels and system, but if it is not working the most efficiently when you need it, you're not getting the benefits.

"If the panels are on the east face in the morning, you are able to use that power when you wake up," he said.

"On the west face, in the afternoon, when you are running the aircon in the summer, getting ready for dinner — that is when you are going to see a big [electricity] bill reduction."

Mr Georgiou said although it was cheaper to install all the panels on the northern side, it was often more beneficial financially for users to go east-west.

"Once you start out with that right panel placement … then you can still add a battery to capture the extra power during the day and use that at night."

He said it was also a good idea to consider what you wanted to achieve from installing solar panels, then tailor the installation to that specific need, rather than relying on a one-size-fits-all approach from installers.

"The common belief that northern-facing is the best in all cases [means] it's cheaper to install, easier to train staff. Overall it's a simpler way of doing things," he said.

"But that benefits the solar companies and the grid, but not the person buying the system."