One simple way to tell if you should get a battery or not

What I have coined as the battery yes/no chart, this is the simplest way to see if a battery is going to potentially work for your home or not.

I've been going deep into battery analysis for newsletter readers lately. So I developed a quick tip to help determine if a home battery is right for you. Take a look at these simple bar charts and you'll see if a battery is going to be a quick no or a yes for your home.

Understanding if there is enough solar energy to absorb and enough grid consumption to offset

The graph below shows the real consumption and solar export patterns of a home I created a battery analysis report for. The bar chart shows the home's energy consumption and solar exports over a year, averaged into a single day, outlining when they export most of their solar energy and consume energy from the grid.

To read this chart, we see on the left that in the early morning hours, this home's grid consumption begins to taper down until about 6am. At that point the homeowners are waking up and starting their day, grid consumption starts to kick in and we see a spike. Good morning. Then from 8am onwards, here comes the sun. The solar system starts to do its things and is pumping renewable energy into the home. There's an overabundance of solar energy and so it's exported to the grid, reaching nearly 2 kWh on average from noon to 1pm.

Now it's 5 pm, it's time to unwind. The family returns home from work and school, the sun is lower in the sky, and solar production is decreasing, while grid consumption is rising. From 6pm to after 9pm it's peak consumption time, and the home is consuming a large portion of its energy for the day. This is a pretty typical energy consumption profile and is a great illustration of "Yes", a battery could be right for your home. If there is no way to reduce your consumption through other methods of energy efficiency, then having a battery that stores the solar energy to discharge it in the evening when peak prices are at their highest can do some small wonders to offset your grid consumption.

When more analysis is needed and a battery is not a simple yes or no

In the chart below we have a grid consumption pattern more like the Westgate, Anzac or Story Bridge, sorry other states I'm not googling a bridge for every state. Below the peaks and troughs are less pronounced, there's still a lot of solar available, but it's unclear if the consumption is high enough on average for a battery to make a monetary difference for this home.

This case is actually pretty common, there is a lot of solar on the roof and all that excess is being exported to the grid for a few measly cents. Fundamentally it should make sense for this home to get a battery and offset nearly all of their consumption, the problem is they might not have enough consumption for the battery to make financial sense. If a battery offsets 5 kWh of energy consumption a day and that energy costs say 30¢ a kWh, that's a savings of $1.50 a day. If we could repeat that result on average every day, that's $548 a year in savings. Now, suppose we purchase a 10 kWh battery and pay $7,500 for it after rebates. Reasonably, we want that battery to break even before the warranty expires in ten years, which means we need to be saving $750 a year in offsets, not $550. But what if the home is on a peak price from 3pm to 9pm, that's 40¢ a kWh, so the costs now change. The home just installed a new reverse-cycle air conditioner to heat the home at night, and they're looking to swap out all of their gas appliances for electric ones. Does a battery make sense now? It's hard to say, and this could go either way. If the home needs to save $750 a year in offsetting their grid consumption, then a battery could well get them there. Maybe not this year but next year, or the year after? As energy prices rise, it's possible that within ten years they blow right past their $7,500 payback goal. A more in depth battery analysis is needed with a more granular look into the possible battery sizes for this home. There just might be a happy medium where a battery does stack up for them, or not!

When your money could be better spent elsewhere

If your energy consumption and solar export profile looks like the graph below, congrats, you are energy efficient! But you are also exporting a lot of solar to the grid for a few cents and your energy provider is going to sell it to your neighbour for 10x that amount, sort of.

In the case of the home above, we actually came to the conclusion that it was in their best interest to get completely off gas as their next home upgrade. Getting off gas was going to pay bigger dividends in the long term for them then any battery could, even with a battery rebate thrown in. Then, maybe down the line, if they can plug an EV in at home around noon, they can soak up their solar energy and continue living the life of model energy-efficient homeowners. So if your energy consumption looks like the above, is a home battery right for you right now? Probably not.

But don't fret, there's probably other great upgrades you can make to your home, like buying a hot water heater and setting it to the afternoon. Making sure your next car is an EV and getting it to soak up your excess solar. There are so many more things any home can do, a home battery is not always the answer.

Would you like to know if a battery is right for your home?

I can run a home battery analysis for you so we can figure out if a battery makes sense for your home.

How it works is we remotely connect to your energy provider over the net, they send us your energy consumption and solar export history for up to years in the past! We then use all that data to simulate how a battery would perform in your home, charging and discharging hundreds of times a year. The end result is that we can figure out what battery size is right for your home and roughly how much its going to save you, based on your actual energy profile and current pricing. No more flying blind, taking the word of an installer who wants to sell you the largest battery they can fit in your home. If you'd like a battery analysis, then reply to this email. It is a paid service, but if you're going to spend $7,000 or more, you should know what to buy and how much that investment will save you.