I mainly use natural gas for hot water (Rinnai System)
My fixed cost per month is $50 and usage is less than that
Is it worth it to switch to bottled gas ? How much does the conversion cost?
Any pros and cons ?
Natural Gas Alternatives - Rising Costs
RealityCheckMate on 29/08/2025 - 23:07
Comments
Firstly go gas supplier shopping to check you are on a decent rate. Could be a quick & easy fix.
LPG bottle prices with genesis are $5.75 / month / bottle rental + $174.99 / refill.
Generally have a two bottle's.
Might be able to do a little better on pricing if you shop around.
Each LPG bottle contains 625 kWh of energy. works out to 28c / kWh.
Look at the number of units of gas on your last bill, and see if you will come in significantly cheaper per month when you do 11.5 + 0.28*(units).
LPG will cost more per unit, and less per day, so what is cheaper depends on how much you use.
If not, stop here, you are better off on natural gas.
If it is within a few dollars I would stick with natural gas, to avoid the conversion costs, and hassle of ordering gas, the space the bottles will occupy etc.
If the difference is large, then you could price up the conversion, Never done it, but going to be at least $300.
As a general note, people are starting to convert gas systems to electric or heapump as gas can be uneconomic (partially if hot water is your only gas appliance). Might be best to avoid sinking money into the gas conversion if this is something that may be viable for you in the future.
We just use 12kg / 9kg bottles (same as for a BBQ) so no rental or delivery costs (unless you want or need to get them delivered I guess).
Also depends how much you use of course - high usage wouldn't be very practical with smaller bottles, in which case renting for $5.75 per bottle per month might make sense, but for us it's not worth it.
Thank you for a very detailed answer.
last months usage was 389 kWh
= $120.42Genesis Gas bill
usage 47 12c/unit
fixed 48 167 c /day
total $110 inc GST
less discount
= $104About $16 per month difference.
That's a nice outcome. You are best off with natural gas, hence no need to make changes or deal with bottles.
If you are in a part of the country with reasonably cheap power, you would be better off to swap to electric. But the payback is going to be many years, so waiting until your gas gear reaches end of life would be prudent.
Thanks. Heat Pumphot water heater is another option when 20 yr Rinnai conks out (touch woood)
Just received another increase
Plus Standard Daily Fixed ($/day)
$1.6751
$1.7505
Plus Standard Variable ($/kWh)
$0.1228
$0.1486
For many gas with an instant gas water heater could work out cheaper than a conventual HWC, and you don't lose energy by having a tank of hot water. It is especially cheap if you are a small house with only 1-2 people in it. We did this and it was very cheap. Electricity is also only getting more expensive, and is more expensive than 28c/kWh. In my area it is 35c . Heatpump HWC are expensive to buy and then install, and also expensive to replace and repair. We decided against it on a new home as it wasn't economic.
There seems to be people lobbying to push people off gas onto electricity, and heat pump HWC. But if everyone did this we llikely wouldn't have enough electricity generation, and it will just push power prices higher due to higher demand. Gas is still seen as a transition energy, and there is also Biogas which is cleaner.
Doesn't help we are also running out of gas
This guys blog has good industry insights about nz running out of electricity generation capacity (a bit doom and gloom but worth a read)
https://newzealandenergy.substack.com/p/is-lng-the-answerWe shouldn’t run out with biogas
We have gas for cooking and instant hot water. I was planning on changing over to electricity in future, but now I'm not so sure. After the last round of price increases, my gas prices are cheaper than electricity. I guess I'm still paying two daily rates, but it's getting less attractive to pay the cost to change everything over right now.
Yes, my weekender runs on LPG for hot water and cooking and it is so much cheaper to run than than it would be if I was using electricity. Overseas they are big on biogas, so if they do run out of of LPG, biogas is likely to replace it. If I was on mains gas instead of bottle gas, it may not be as attractive, as the daily rate for having a main gas connection is high relative to the amount of gas used. But mine is a new house and they still installed gas appliances
What about Heat Pump heater
but but…. they said solar and wind are free so it will bring down energy prices.
LOL. Just like energy reforms were supposed to bring down prices and increase generation. NZ used to have some of the cheapest power prices, now they are very expensive. Instead profits just head offshore. But if people have solar and can generate their own power, then it could be a saving. But the capital costs are very high. Plus the more people that do that, the less people will use the grid power, so less money for investment.
@nzmax: Out of interest, if the energy reforms had not happened, what would the average per kWh prices for electricity be today?
@Alan6984: Can look at overseas countries like Canada. Quebec for example only pays 7-8c per kWh for hydro and state owned
Can look at overseas countries like Canada. Quebec for example only pays 7-8c per kWh for hydro and state owned
Overseas is not overly relevant to me - I can't buy my power from a Canadian provider.
So, what would it have been here compared to what it was here before the reforms, if the reforms hadn't happened?
I'm trying to understand how much the reforms you mentioned have actually increased prices here.
@Alan6984: The Commerce Commission may have that information. We can only look at prices overseas where they didn’t have the reforms and the Commerce Commission would probably do that too as they did that for supermarket prices when it found we were over paying.
Standing losses are pretty small.
Current standards require new 180L cylinder to be built such that they loose less than 1.7 kWh of heat / day (under test conditions).
My power is 19.79c / kWh (incl GST), so standing losses would be about 34c / day. Less money than renting a pair of bottles in many cases.
On Electricity prices increasing, while true, you may have missed that natural gas prices have increased dramatically more. I don't track LPG prices, but think they have also have quite an increase also. Was only 3 years ago you could get a 45kg swapped in Christchurch for $99.
Given we are running out of natural gas much faster than expected, I would expect to see natural gas inflation continue to outstrip power price inflation. LPG price inflation is tied to oil prices, so harder to predict.
There are some regions with more expensive power (north-land as an example), and some lines companies with massive charges (THC as an example), which could influence decision making.
I'm going to be on a standard user power plan regardless, but for those who are on low user plans, lower daily charge & higher unit charge can make gas relatively cheaper per unit. Low user chargers are currently being phased out, and this distortion is one of the key reasons why.
"But if everyone did this we llikely wouldn't have enough electricity generation"
Not everybody is going to get off gas all at the same time.
Even if they did, residential gas use is small 4-5 PJ of Natural gas and 3.8 PJ of LPG. About 2400 GWh / year. Even if we use 1:1, we would only need to increase our generation by 6% to cover this.
I'm in the industry, and got 600 GWh / year of project consented this year… Lots of others are doing the same.
On gas being a transition fuel, In short, not for NZ. (gas in this context is natural gas) Our natural gas is running out faster than expected, we can't move to use dramatically more gas. We had issues with shortages earlier this year. We could build a LNG import terminal, but thats $200m to $1b.
Yeah, biogas is a thing, but it's production is already common at waste water plants, so not massive opportunity to scale this up. Also it's quality is such that it is typically not injected into the gas network, instead being either flared, or burnt in a generator onsite.
I'm in the industry, and got 600 GWh / year of project consented this year… Lots of others are doing the same.
This is the problem, NZ has quite a lot of consented generation (wind farms, solar etc.) but that's not turning into actual power generation as there's very little incentive for the gentailers to increase supply, and thus lower costs.
@mpc: There has been a significant uptick in new generation getting built over the last couple of years. Decade prior to that was very slow.
Some notable projects:
Tauhara Geothermal Power Station, 1,420 GWh of electricity per year, Opened Nov 2024.
Utility scale solar only really kicked off with the Loadstone Kaitaia project in 2023.
179 MWp of utility scale solar over 5 projects complete (only counting 10 MW+ projects.) in the ballpark of 280 GWh / year.
The following are under construction:
- Kowhai park: ~280 GWh / year
- Tauhei ~280 GWhWind is also seeing a boom, both the following are under construction:
- Kaiwaikawe Wind Farm ~221 GWh
- Kaiwera Downs Wind Farm (Expansion) ~525 GWh (for a total of 673 GWh)The listed projects alone are enough to replace all of our residential gas use in NZ.
Bigger challenge comes from getting industrial heat off gas and coal. The energy amounts are orders of magnitudes higher.
Anyone else received notice of rate changes - increasing yet again
I got an email of gas going up again too.
We used to be on mains gas, and now have bottled in our place - I can't say I notice any difference at all, except it's cheaper without having to chip in for the infrastructure.