Most people install solar panels and batteries because they want to reduce their electricity bills and be more self‑reliant. But once the panels are on the roof, how do you know whether you are getting the most out of them? That’s where the solar spot comes in.
We use a simple visual with four colours:
- Green – Solar energy you use directly in your home or business (the sweet spot).
- Grey – Solar energy you export to the grid during the day and then re‑import later at night.
- Red – Net energy imported from the grid.
- Yellow – Net energy exported (you produce more than you use).
The perfect solar spot shows a lot of green. That means you are using the energy your system produces when it produces it, and not relying heavily on the grid.
How we help clients analyse their data
Every property is different. We utilise detailed electricity usage data to gain insight into what happens in your home or business throughout each day and the year.
What is interval data?
Importing too much electricity.
Your electricity meter (if you have a smart meter) records your usage every 5, 15 or 30 minutes. This is called interval data. With your permission, we can securely access up to two years of history. Why two years? Because energy use changes with seasons (think air conditioning in summer or heaters in winter) and even with habits (school holidays, irrigation cycles, harvest periods).
We use this data to build personal daily usage curves:
- Weekday vs weekend – Homes often have a different pattern when people are at work or school compared to when everyone’s home.
- Summer vs winter – Air conditioners, pool pumps, heaters, and hot water all shift usage patterns.
We then overlay your solar production curve (which shows when your panels produce power) to see how well your usage aligns with your solar output.
Reviewing the Solar System Size
Exporting too much electricity
If you have had your solar system for a while, your electricity needs might have changed. Additionally, solar panels have become significantly more affordable, making it easier to install larger systems.
On the other hand, the generous feed-in tariffs are a distant memory. Now, it is only a few cents, so it is essential not to oversize the system.
And then there is reduced output. Over time, solar panels gradually lose some of their production capacity. Therefore, it is beneficial to review how much they are currently producing compared to their full capacity. While interval data may not reveal gradual drops, it can highlight a sudden decline, which may have occurred due to damage from a hailstorm.
Extending solar usage with a battery
Good production, but losing benefit through night usage
Every household needs energy at night. This is where batteries come in.
The solar spot on the left shows that the solar system produces about the right amount of energy. However, most of it is fed into the grid and then imported back for use at night.
A battery stores excess solar energy during the day and releases it when the sun goes down. This can significantly reduce the amount of electricity you import from the grid (the red area of the solar spot).
While it is excellent to cover your total electricity consumption through solar, if you export excess solar during the day and reimport it at night, you pay the difference between the feed-in tariff and the cost of electricity, a significant portion.
Batteries can eliminate a lot of that.
Why now is a great time
Government rebates currently cover up to 30% of the cost of a battery. These rebates decrease each year, so the savings are currently at their highest. For many households and businesses, this rebate significantly reduces the payback time.
How to move more usage into the solar window
In addition, we look for ways to shift some of that usage into the time of day when the sun is shining:
- Hot water systems – Can often run in the middle of the day.
- Pool pumps – Timers can push filtration cycles into solar hours.
- Appliances – Dishwashers, washing machines, and dryers often have delay‑start functions.
- EV charging – If you have one (or plan to get one), charging during the day is ideal.
Sometimes, it’s as simple as adjusting when you turn things on. At other times, we recommend adding timers or smart plugs so you don’t have to think about it at all.
Choosing the best electricity tariff
One last thing: by analysing your detailed interval data, we can also check whether you are on the best electricity tariff available from your retailer. Different tariffs work better for different usage patterns (flat rates vs time‑of‑use rates, for example). This analysis often identifies additional savings beyond what solar energy alone delivers. (We’ll write a detailed blog about tariffs soon.)
The takeaway
Near perfect with a bit of import
The perfect solar spot is primarily green – using as much of your solar power on-site as possible. We achieve that by:
- Analysing up to two years of detailed interval data to understand your habits.
- Reviewing the production of your solar system and possibly resizing it
- Adding a battery when it makes sense – and right now, rebates make it more affordable than ever.
- Finding ways to shift or automate some usage into solar hours.
- Checking your electricity tariff so your solar system works hand‑in‑hand with your plan.
Want to see your solar spot and find out how to improve it? Get in touch.