Hardly any New Zealanders will remember the summer of 2023 with fondness. The last couple of weeks (Feb 6- Feb 16) have wreaked an unexpected level of havoc in the country. And while lost or missing family members will always be the most dreadful effect of Cyclone Gabrielle, it has caused other problems too.
A major impact of the cyclone has been power outages. As soon as Gabrielle hit, a staggering 225,000 people lost power, and many of them had to wait for days for the grid to come back to life. This is touted as the biggest natural disaster in a century, and with a worsening climate, we can expect this to happen again.
Naturally, we have received an enormous amount of enquiries from people all around Aotearoa. Most enquiries are from homeowners wondering if they should get a portable petrol generator or a solar battery, in case another disaster strikes and takes away power, one of our most basic necessities.
Therefore, we decided to write this piece to help make it easier for you to choose. We know what is at stake when a disaster like this occurs, and that’s why we have created this article without any bias, so you can do what’s best for you and your family.
Both fossil fuel generators and solar batteries (like the Tesla Powerwall) have their own pros and cons. And while it seems counterintuitive to recommend fossil fuel generators for preparedness against extreme weather events, uncertain times often call for difficult measures.
Let’s go ahead and compare petrol generators and solar batteries in all aspects.
Small to Medium Petrol Generators Available In NZ
A petrol generator is similar to your car’s engine. Just as your car’s engine powers the audio system, lights, and other electronics in the car, a petrol generator powers appliances in your home. Generators have been around for very long, and while older models were noisy and polluting, newer models are quieter, relatively cleaner, and also more compact.
A typical petrol generator
Let’s compare some popular models:
|Model & Brand
|Price (not including installation)
|DeWALT 2200W Inverter Generator
|2.2 kW Starting Watts with 1.8 kW running
|8hrs+ runtime at 50% load, per 4L of fuel
|Light, easy to move
(20kg dry weight)
Simple recoil start system
|Honda EU22i Inverter Generator
|2.2 kW Starting Watts with 1.8 kW running
|15 hrs @ ¼ load, per 3.6L of fuel
Low oil alert system
|Honda EU30is Inverter Generator, 2 Wire Auto-Start
|3 kW starting, 2.8 kW continuous
|20 hrs @ ¼ load, per 13L of fuel
|Electric start including battery,
Recoil start for back-up,
Whisper quiet at 51-58dBA,
4 year warranty
Please note that we do not promote these petrol generators, and this list is merely to help you gauge the market.
The demand for petrol generators has dropped in recent years, especially with the onset of solar batteries. Despite that, generators offer some unique advantages over batteries. Let’s take a look:
Advantages of Petrol Generators
No sunlight needed
Unlike solar power, petrol generators are not dependent on weather conditions and day-night cycles for power generation. Sure, generators do need petrol to operate, but you can have more control on when and how much petrol you want to fill up.
Use fuel from your car
In the event of an emergency, driving to the petrol pumps may not always be possible. Thankfully, you can use fuel from your car (if it’s fuelled up) to run your generator, thanks to the use of a similar engine. You can even use your car’s petrol for weeks if you use power for essential power use. Keep in mind that a lot of cars have anti-siphon devices, check if your car is one of them by consulting the specs or calling the company.
A lot cheaper
While solar power saves you substantial amounts of money in the long run, petrol generators save you on the upfront cost. Generators are significantly cheaper than solar tech, sometimes costing just a fraction. However, they are not a smart investment in the long term as they have a considerable operational cost.
Small generators are portable
Solar batteries and panels can be bulky, heavy devices which are normally fixed to your roofs and home walls. They are difficult to move around once installed. Smaller petrol generators are, on the other hand, impressively portable. They even come with wheels for easy movement. You can even lend your generator to a neighbor or a friend if needed, unlike solar equipment.
Drawbacks of Petrol Generators
Difficult to fuel in strongly affected regions
Petrol generators may be easier to refuel instantly, but this dependence on a non-renewable source is also its major limitation. In areas that are devastated by a natural calamity, getting petrol may often be the biggest obstacle.
A petrol pump affected by a power outage in Hawke’s Bay (source: RNZ)
In several parts of NZ, petrol pumps saw enormous queues of people looking to fill up their generator tanks. In many areas, fuel pumps themselves are victims of power outages, unable to fill up anything in cars or generators.
Petrol generators require maintenance
Here’s a basic rule about machines - wherever there are moving parts, there are maintenance requirements. And petrol generators are basically engines with parts that move and rub against each other thousands of times every minute. Petrol generators require a significant amount of maintenance - from oil changes to air and fuel filters and spark plugs.
As mentioned before, this may not be an important criterion during a natural disaster, but it is still something that cannot be ignored, especially in the long term. Owing to their use of fossil fuels, petrol generators emit carbon dioxide, carbon monoxide, and other gases that are proven to directly impact our climate. Moreover, inhaling fumes from the generator can also cause serious ailments. Thankfully, some models like this Honda have relatively lower emissions.
Pull chain generators can be hard to start
Many modern generators come with a starter battery. Similar to your car engine, these can be started with the turn of a key or the pressing of a button. However, many simpler models still use manual cranking - meaning you have to pull a chain vigorously to start the engine. This may not always be easy, especially for older people or people with health conditions.
We know that generators will cause noise and fumes when operational, and it is definitely not a good idea to place it in the house, or even in the garage. If you do place it in the garage, you will need to keep the garage space ventilated, which may be difficult in stormy conditions.
If placing the machine outside, you will need a case/box to cover it with. These cases are available from the manufacturers at an added cost, and are designed with sheltering and ventilation both in mind.
- Keeping fuel in a jerry can will go off and become unusable after 3 to 6 months. A fuel stabiliser can be used to help the fuel last longer.
- Larger generators stored outside will need to sit on a concrete pad. There is added cost and work involved in building a concrete pad/base.
- You can plug portable generators directly into a regular home outlet. But permanently installed generators need to be hardwired into your home grid. Unless you are well versed with electrical work, it is wise to get an electrician to hard wire it into the house switchboard.
- Most petrol generator brands will specify Grade 91 petrol only, you cannot use 95/96 in its place. Make sure you check the requirements before fueling.
Solar Batteries With Backup Capability Available NZ
Unlike generators, solar batteries are chemical devices with no moving parts. They take energy from a solar power system, but can also use grid power to charge.
A typical solar battery
Let us take a look at the available solar battery options in NZ, along with the specs and the pricing.
|Brand & Model
|Usable Storage Capacity
|Approx. Installed Price
|Tesla Powerwall 2
Multiple control modes
|Indoor and Outdoor installation.
|BYD Premium HVM
3 phase compatible
|Huawei Luna2000 10kWh
3 phase compatible
Advantages of Solar Batteries
Quieter and cleaner operation
Needless to say, batteries are much cleaner and quieter than combustion engines (the main reason electric cars are slowly taking over). This allows you to install a battery inside your home without worrying about fumes or noise. Naturally, they are also far better for the climate. With the correct equipment, EV owners can even use their EVs as a battery source during outages.
Modern solar batteries use intelligent software that can switch the battery on and off as needed without you even noticing. Many batteries also have the feature of load limiting, where you can decide what to run on the battery and what not (keeping aside a power hungry device during an outage). While some petrol generators also have auto switching options, batteries can have smarter features in them.
Remote app-based monitoring
Most solar batteries can be monitored via a smartphone app or website, where you can see if the battery is operational or on standby, and how much energy is used, or how much remains.
Natural disasters are a horrifying but unavoidable reality. One of the major outcomes of a natural disaster, such as the recent Cyclone Gabrielle is its impact on the power grids, rendering thousands of families without power.
Petrol generators and solar batteries can be extremely useful to fulfill basic power needs at such times, and many people wonder which one is the better choice. Both the options have their own advantages and limitations - petrol generators can be cheaper and easier to refuel, but batteries are quieter, cleaner, smarter, and even better for the environment.
Overall, batteries are more beneficial to its users and the planet in the longer term, which is why it is the preferred storage solution even for large-scale renewable plants.
There is a third option that combines some of the advantages of both petrol generators and batteries - portable lithium-ion batteries. Sometimes also known as portable solar generators, these compact devices can run essential appliances like laptops, phones, small fridges, TVs, etc. for a few hours or days depending on capacity. Some examples include products from GoalZero, EcoFlow, etc.
Whichever option you choose, one thing is for certain - it is best to be prepared!