Guides & Expert Analysis
In-depth comparisons, buying guides, independent analysis and interviews with experts for NZ homeowners.
By Carolyn Cox · Sustainability Expert, 25+ years
Comparisons
Head-to-head analysis of the brands available in New Zealand. Independent and data-driven, with a clear verdict.
ComparisonWhat is COP? Understanding Heat Pump Efficiency
What COP means for hot water heat pumps, what counts as a good COP in NZ, and how to compare brand claims fairly.
ComparisonHeat Pump vs Cylinder vs Gas: Which Hot Water System is Best?
An independent, data-driven comparison of every hot water option available in New Zealand: costs, 15-year total, environmental impact, and who each system suits best.
Buying Guides
Everything you need to know before making a decision.
Buying guideShould I Switch from Gas Hot Water?
The short answer: almost certainly yes. Here's the full picture: costs, savings, the disconnection process, and which heat pump systems work best for gas switchers.
Buying guideHot Water Heat Pumps Explained
Everything to know before you spend a cent on a hot water heat pump. NZ expert Annie Jefferson in conversation with Carolyn Cox, with video, key takeaways and transcript.
Buying guideYour Guide to Hot Water Heat Pump Installation
A buyer’s guide to getting your heat pump water heater installed properly - so it delivers great hot water and a lower energy bill.
Buying guideHow Much Does a Hot Water Heat Pump Cost in NZ?
2026 pricing guide — what you'll pay, what's included, what affects the price, and how long it takes to pay for itself.
Buying guideGreen Finance Guide: Funding Your Electrification
All five major NZ banks offer low-interest green home loan top-ups for electrification upgrades. Combined with government grants, you can make the switch sooner - and save thousands.
Buying guideHow to Create an Efficient Electric Home
Home-energy adviser Tim Forcey on how to create an efficient electric home, with video, key takeaways and transcript
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