Don’t burn out your battery chasing pennies — here’s why energy trading hurts your wallet

Buying a Battery Just for Energy Trading? That’s Like Buying Tyres for Burnouts


Every now and then, someone proudly tells us they’re getting a solar battery so they can “make money” trading power back and forth with their retailer. The idea is simple: charge the battery cheap, discharge it when the retailer pays more, and profit!


Except… in the real world, that’s about as smart as buying a set of expensive high-performance tyres just to do burnouts in your driveway. It’s fun in theory, but it’s expensive, it’s wasteful, and it leaves you with a lot less tread than you started with.


Better to buy new tires for getting from A to B; and better to get a solar battery for energy resilience and decreasing demand on the grid in the few hours after sunset.


A Common Bait And Switch


One of our favourites is when clients say: “I want to make sure my battery is charged by 5 pm so I can export the energy for 20 something cents."


Great idea… if your goal is to make less money. Because during those same hours, the import rate could be around 40c.


So let’s do some Year 10 maths:

  • If you use your own stored energy between 5pm - 9pm, you’re avoiding paying 40c/kWh (ish).
  • If you export it, you might be lucky enough to earn 20 - 30c, depending on your retailer.


That’s right — you’re literally selling something for less than it’s worth to you.

That’s not energy trading. That’s a slow leak in your wallet.


The Real Cost of “Burnouts”


Batteries have a finite number of cycles in them. Every time you charge and discharge, you’re wearing down the chemistry.


Most warranties cover one full cycle per day. Go harder than that with energy trading, and you’ll hit two problems:


Warranty woes – your warranty will 'run out of tread before' 10 years rolls around.

Premature capacity loss – that shiny 12 kWh battery might be holding 9 kWh before you know it.


It’s a bit like owning a V8. You can accelerate quickly, and hit some high speeds. But floor it too often and you end up paying for it in trips to both the gas station and tyre shop.


Why the Payback Just Doesn’t Stack


Let’s be generous and say you’re trading at a net gain of 22 c/kWh.


With a 12 kWh battery, you might make $2.64/day, or $963/year. That’s before you factor in efficiency losses (you don’t get 100% of what you put in) or degradation.


If the battery cost you $15,000, that’s a 15-plus-year payback — if the battery isn't limping for the last leg of the marathon.


Smarter Uses for a Battery


Instead of playing amateur energy trader, use your battery for:

  • Self-consumption – keeping your own power bills down by using what you generate.
  • Backup power – so when the lights go out, yours stay on.
  • Load shifting – charging cheap before the morning peak time to avoiding paying the expensive peak morning rate, typically between 7am and 9-11am.


Those uses get you real value without turning your battery into a worn-out set of burnout slicks.


Final Thought


If you’re buying a solar battery purely to export for a few cents’ gain, you’re not trading — you’re giving the retailer the better deal. Keep the 35c power for yourself, skip the “tyre burnouts,” and let your battery live a long, productive life.

By looka_production_130270016 December 23, 2025
Solar panels are so cheap now that even selling excess energy back to the grid at so-called “peanut” rates can still be a very good investment. So let’s talk about solar the right way — not emotionally, not politically, and not based on what your neighbour reckons. Most people say, “Selling solar to the grid isn’t worth it. It’s peanuts.” And our response is always the same: “Nothing wrong with peanuts” Reality is, solar should be considered in the same way all investments are considered. The question is - What am I spending, and what am I getting ? The Abraham Argument (sorry, its a bit of fun) In the book of Genesis, Abraham argues with God over the prospect of saving Sodom and Gomorrah from a terrible punishment. Moses asked god - “Would you save the city for 50 righteous people?” “How about 40?” “30?” “Come on… 20?” “Wait — before you send the fire — how about 10?” That same bargaining logic works beautifully with solar. Let’s assume the absolute worst-case scenario and argue backwards. Check Out Abrahams Sales-Pitch Imagine this: 18 solar panels Cost: $5,000 (totally unreasonable) Annual generation: ~10,000 kWh Every single unit sold to the grid Buyback rate: 17c per kWh Those panels would pay you $1,700 per year in solar buyback credits. No self-consumption. No batteries. No optimisation. Just exports. That’s under a 3-year payback . What do you reckon? Would you do it? Moses - “I’ve got my hands on the stone tablets. And I’m telling you – you can’t get 18 panels for $5,000. But let me ask you…” How Many Donkeys Would You Trade For 18 Panels? If exports alone deliver $1,700 per year in export credits, would you buy 18 panels if they cost: $12,000? (5.9-year payback) $14,000? (8.2-year payback) How about $16,000 and some unleavened bread? (9.4-year payback) ... $16,000 is about what 18 panels cost for most homes. You can forget the unleavened bread. And by the way, Abraham forgot to tell you 👉 $1,700 is the worst this system could save you. Why You'll Save More Than Moses Reckons If you sell solar to the grid, Moses already told you its worth about 17c per kWh (give or take). But the solar you actually use is worth more! It’s worth your retail rate — typically 30–40c per kWh incl GST. That changes everything. Also, If your roof is a decent north-facer with more than a 10° pitch, 18 panels won’t generate 10,000 kWh. They’ll generate more . Good roofs regularly see 11,000 kWh with 18 panels (460w assumed). Great roofs can push 12,000+ kWh per year! Tearing Down The Strawman Argument In the real world: 18 panels typically save ~$2,000 per year without a battery Add a battery and that can push closer to $3,000 per year (book a consult with us to iron out the finer details). So, if Abraham were here, he wouldn’t be arguing about buyback rates. He’d be covering the city in panels to power his DC grain mills and DeWALT power tools. (That's how they built the temple so quick. DeWALT all day)! Because if you can spend $16,000 today and save $2,000 per year minimum , you’re looking at roughly a 7–8 year payback . Over 25 years? That’s $50,000+ in savings when you bake in 3% inflation . Closer to $70,000 if you don't subtract the cost of adding a battery in 5-10 years. But we think the battery will be necessary, because the buyback rates will eventually trend downwards - and you can't expect $70,000 in savings without adding a battery when they become a necessity. The Takeaway Solar exports aren’t the dream scenario. They’re the floor . And when the floor already looks this good… the upside takes care of itself. Disclaimer: You may not be able to sell all of what 18 panels can generate. There are limitations. However - those limitations become entirely irrelevent if your home pulls ~2.5kW of energy during the peak hours between 10 & 2. It's not all that hard to get your home doing this. Pool Pump, Spa, Hot Water Cylinder, Aircon in summer + Fridge and Freezer all add up to a hell of a lot more than a 2.5kW energy demand. And so; the export limit is mostly irrelevant on homes with 18 panels or less. Once you have more than 18 panels, the story changes - but the story is also developing, because more and more networks are unlocking 10kW buyback on one phase, instead of the standard 5kW buyback per phase. And of course, if you have multiple phases (2 or 3) you can get away with 25 - 35 panels and experience zero limits to how much you export.
By looka_production_130270016 December 22, 2025
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