Solar's giving me the warm fuzzies

Has solar and a battery storage system been worth it for my family and I? Short answer: Yes, especially since we’re not planning to move anytime soon.

Now that we’ve had our home solar and battery setup for just over four years, I’ve taken a quick look over the weekend to see how the numbers have stacked up. I thought I’d post these details, as a few folk I know are now seriously looking at installing solar this year, given the cost of electricity in New Zealand is putting pressure on their budgets.

My family and I installed our system in 2022. It includes 5 kWp of solar panels, a 5 kW inverter, and a samll 5 kWh battery. The solar panels and inverter cost NZ $8,152, and we added the battery for an additional NZ$7,014 (I’d say these costs have decreased since 2022).

Based on our usage, the system saves us roughly NZ$1,173 each year by reducing how much power we draw from the grid. We also earn around NZ$187 annually from feeding excess energy back into the grid at 8 cents per kWh.

I’ve paired this with a bit of home automation to help time-shift some of our larger home appliance loads. By running things like our hot water cylinder late in the evening, during my electricity retailer’s free power period, we avoid about NZ$722 per year in hot water electricity costs. Also, charging our EV during these same off‑peak hours saves another NZ$1,084 annually – give or take. If you’re interested in the details, I’ve written more about our home solar setup under tag #Solar

Putting all of that together, we avoid about NZ$2,980 per year ($1,173 + $722 + $1,084) in electricity costs and earn NZ$187 from exported power. At today’s prices and based on what we paid in 2022, the full solar-plus-battery setup works out to an estimated 11‑year payback period – around six years for the solar portion and five for the battery.

Aside from the dollar benefits, there are one or two functional benefits too. The mobile app highlights how and when energy is being used in our home, which is a nice touch as it means we’re more mindful of when we choose to run some of our larger appliances, like the oven. Surprisingly, one benefit I’ve found is that I feel far less worried about my family leaving the lights or TV on after they’ve left a room (my dad really needed this for when I was a kid!).

So, has it been worthwhile?

For us, absolutely. If nothing else, installing solar was the catalyst to find ways to be smarter with our energy usage and, where possible, automate ways to save money.