A Timaru solar installer says neither Labour's nor National's proposed home solar subsidy schemes would cover the actual cost of installation, as both parties push competing energy policies ahead of the election.

Terry Patterson installs solar panels in the Timaru area. He told RNZ's Morning Report that a typical home installation costs between $22,000 and $27,000 — far more than either party is offering RNZ.

A standard home system needs roughly five kilowatts of generation capacity. That means about 15 to 16 panels, an inverter (the device that converts solar power into usable electricity), wiring, and sometimes a switchboard upgrade. These parts add up to well beyond what either party has promised.

Labour unveiled its SolarSaver package this week, a $160 million policy aimed at reducing power bills 1News. The scheme has two parts: Crown-underwritten loans issued through lines companies and repaid via power bills, and a $3,000 kickstart subsidy for low and middle-income families installing solar RNZ. Labour's goal is to double the number of New Zealand houses with rooftop solar Facebook/NZ Labour Party. An earlier account from Carbon News described grants of up to $4,000 per household (split between $2,000 for panels and $2,000 for a battery), though the figures RNZ and 1News confirmed this week put the kickstart subsidy at $3,000 Carbon News.

Patterson said $3,000 "isn't enough to meaningfully help" when installation costs run into the tens of thousands. He was also unconvinced by Labour's renter-focused element, which would let renters use the kickstart subsidy toward plug-in solar units. Those devices generate only 600 to 1,000 watts — enough to run a fridge or one similar appliance, not enough to seriously reduce a household's overall power grid use.

National's competing offer is the Home Energy Fund, which provides low-interest loans covering solar panels, batteries and insulation. Repayment happens through rates rather than power bills National Party RNZ. National MP Simeon Brown promoted the fund on Instagram on 24 June, saying it would let households avoid the upfront cost of solar installation Instagram/Simeon Brown. Unlike Labour's package, National's fund bundles solar with other home energy efficiency measures. Because repayment happens through rates rather than a direct subsidy, homeowners still carry the full installation cost — it just gets spread over time.

Patterson's key technical point concerns battery storage. He described it as critical to solar economics — particularly for households away from home during the day. Export tariffs paid to solar customers who feed excess power back into the grid sit at 8 to 12 cents per kilowatt hour, he said. That's against retail power prices of 34 to 38 cents per kilowatt hour for standard use. Without a battery to store daytime solar power for evening use, that price gap eats into much of the financial case for going solar in the first place. Neither party's core subsidy prioritises battery storage at the scale Patterson says is needed, though Labour's $2,000 battery component and National's Home Energy Fund both allow battery costs to be included.

Patterson pointed to Australia's home battery adoption as a comparison point — roughly 450,000 battery installations there in the prior 12 months. He said installation activity in his Timaru-area customer base continues but at a slower pace than before, even as some customers report power bills well over $1,000 a month.

Both parties' policies follow earlier regulatory moves on solar. In mid-2025, the government proposed changes to the Building Act to clarify that building consent is not required for rooftop solar installation RNZ. That change was aimed at cutting a different kind of cost — the compliance overhead rather than the capital outlay Patterson is describing.

The gap between Patterson's installer-level cost data and the subsidy figures both major parties are campaigning on looks like a simple arithmetic problem rather than a partisan one. Whether Crown-backed loans repaid through power bills (Labour's approach) prove more attractive to households than rates-repaid loans bundled with insulation (National's approach) will likely depend on interest rates, repayment terms and eligibility criteria that neither party has yet fully detailed.

For an installer working with customers on fixed incomes and existing four-figure power bills, the more immediate question is simpler: whether either scheme closes the gap between a $3,000-to-$4,000 subsidy and a $22,000-to-$27,000 installation.