To get the most out of your energy efficiency improvements at home, it pays to check that you’re on the right power plan. This is how you guarantee you’re paying the lowest price for what you’re using, and how you’re using (or generating) it.

Check you’re on the right plan for your home

The Electricity Authority has a free tool to help you compare and switch plans, along with helpful information to help you take control of your power bills.  

An efficient home is greater than the sum of its parts  

Efficient technology and appliances use less energy to get the job done. So much so that switching out key household tech for more efficient options can save some homes over $1,000 a year.  

They also save a huge amount of energy on a national scale — with Kiwi homes and businesses collectively saving enough energy to power 36,000 homes in the year leading up to April 2025 — just by purchasing more efficient models of household appliances. This adds up to around $35 million in avoided energy costs for New Zealanders. 

Naturally, we put time and consideration into planning big upgrades, often one at a time. We might prioritise where we’ll make the biggest long-term savings — like a heat pump in the living room, new hot water system, or installing solar. We might also look at improving comfort and quality of life — like double glazed windows, or retrofitting insulation. The best solution is unique to your own home and lifestyle.   

But to get your home really humming with efficiency and reap the rewards, you need to zoom out and look at its overall ‘pattern’ of energy use. With this bigger picture view, you can choose your power plan to suit - rather than tackling your energy costs one appliance at a time.

Your power bill structure matters more after a big energy shift

The pattern of energy use in your home is shaped by the age, energy supply and design of your house, how you and the people in your home consume power, and the individual appliances doing their jobs. When you make a big change to how you use, generate or store energy in your home, that pattern changes.  

With every major shift, your energy plan may need to change to make sure it’s adapting to your new energy pattern — because the option that works out the cheapest for you might have changed. 

Modern power plans aren’t one size fits all 

When you start using less energy in your home, the balance between your fixed daily charge and variable rates matters more. This is because low-user plans tend to have lower fixed daily charges, but higher variable usage rates (the amount you pay per kWh of power used).  

Efficiency improvements (which reduce the number of kWh) can change which plan type is better value, because they may influence: 

  • how much electricity you use overall 
  • when you use electricity (day vs night, peak vs off-peak) 
  • whether you export electricity (through solar buy-back). 

Modern retail plans price things differently. Time-of-use plans, for example, can offer cheaper (or sometimes free) electricity at certain off-peak times, but often cost more at peak times - so benefits depend on whether you can shift usage.  

Time of use plans can amplify your savings

Switching your appliances to electric options often increases electricity use while reducing the cost of other fuels like natural gas — especially if you’re switching out big energy users like hot water heating, space heating, or introducing an EV. A time of use plan can help you save on running costs if you are able to shift some of your energy use to off-peak times when electricity is at its cheapest — like charging your EV overnight. If you can’t shift your energy use to off-peak times, you run the risk of paying more on a plan that rewards a behaviour you’re not doing.

There is a huge amount of value in shifting electricity use away from peak demand periods, beyond your own four walls.  EECA’s recent research shows that up to 25% of peak electricity use could be shifted away from peak times — saving New Zealanders almost $3 billion in avoided investment.*

Find out more about time of use plans(external link)

Get the most out of solar

Time-of-use style plans can also be particularly beneficial for homes with solar and battery systems, because batteries can store the free energy generated during the day to power the rest of your home during evening peak times.

Billy helps you make sense of your bills

Billy is a free power comparison tool for whenever your power feels too expensive, too confusing, or both. Billy can help you make sense of your bills, compare plans and switch providers, and learn more about how different plans could help you save.   

Checking is quick and easy — either upload a recent power bill or answer a few simple questions to give Billy an idea of your household’s power usage. Billy will search for relevant plans from power companies, and if there’s one you like the look of, you can switch easily. 

Check you’re on the right plan with Billy(external link)

Get the most out of your improvement 

  • Solar — Solar adds another dimension: generation. This only happens during daylight hours, so a flat rate plan makes sense – so you aren’t spending more during peak evening hours. You also may be able to export any energy that you aren’t using to the grid, and what you’re paid for this export depends on your plan so it pays to shop around.

    Make the most of your home solar system

  • Batteries — Batteries can be financially beneficial if they are paired with solar and a time of use power plan. You can maximise savings by charging with cheap solar or overnight and using that stored energy at peak times when prices are higher – but you’ll need to check you can access these.  

    Planning the right home solar system for you

  • EVs — Smart chargers can delay charging until off-peak times, prioritise solar power, or respond automatically to electricity prices.

    Learn about smart EV chargers

  • Hot water — Water heating makes up around a third of your household energy use. This means that an efficient system, like a hot water heat pump, could potentially drop your energy use significantly, and make a low-user plan more suitable.

    Hot water heat pumps for your home

  • Space heating and insulation — Heating and cooling makes up another third of your energy use, so an efficient heat pump, or improved insulation, could be an opportunity to save. The time of day that you run your heat pump could impact what you pay, making a time of use plan more suitable.

    Heat and cool your home efficiently

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