no power bills
Off grid solar
Many people aspire to be completely off the grid. Simply, this means installing a big bank of batteries, and enough solar panels to manufacture all the electricity you need and then cutting your tie to the grid.
Completely off grid and self-sufficient
Producing your own power can give you the freedom to live just about anywhere. You will avoid the huge expense of getting the grid connected if you choose an off grid solar power system. This can save you tens of thousands of dollars if the nearest grid connection is a long distance away.
You’ll have no power bills—ever! However, you will have to factor in the price of replacing your batteries when they wear out—which is usually after 8-12 years depending on the quality of the battery.
You will be independent, self-sufficient and resilient. These last three benefits are more than enough for many people. If this sounds like you, then talk to us. We are specialists in large and small off grid solar.
If you are already connected to the grid or you can look out your window and see a power line not too far away, then grid powered solar is for you.
Making sense of
off grid solar
The costs
It usually costs $30,000 - $60,000—and more, to go completely off grid. This is triple the cost of staying grid-connected and installing solar. There are several reasons why it’s so expensive; First, because of the need for a large battery bank to tide you through the winter months when the sun doesn’t shine very much. Second, because of the need for an expensive inverter/charger to manage your solar generation, power consumption, and generator connection (yes, you will need a generator). Third, because of the dedicated space required for battery storage. And fourth, because of the design and installation cost which is much more complex and higher than that of the simpler grid-connected systems.
Design complexity
An off grid system must be designed correctly. You need to think through all the appliances you will want to run to determine the total daily load that you will need to draw from your batteries. Get this wrong and you could end up running out of power or shortening the life of your batteries prematurely. Off grid solar is not a ‘set and forget’ type of system. You will need to manage your load, be aware of when the sun is shining, and be prepared to maintain your system over the years.
It can’t run everything
Off grid systems have a finite power limit. That limit is set by your battery and inverter/charger size. Unless you install a very large system there will be some things you should not expect to run from off grid solar. These are the types of loads that use a lot of electricity. For example, we advise people not to run an electric oven, dryer, heater, spa pool, swimming pool, heat pump or charge an EV.
Having said the above, there are some very good reasons to consider going off grid.
Types of equipment
Off grid solar is much more complex to design and set up than a grid-connected system. There are additional components required. Obviously, there is the battery bank which is much larger than any battery that you might find in a grid-connected system.
While a hybrid grid-connected system might have 3-14 kWh of lithium batteries, an off grid system typically has 16 - 32 kWh of lithium batteries. Other components required include charge controllers, a battery monitor and a generator. Because off grid systems must be custom designed they need to be designed by a professional who has plenty of off grid experience. McNae Group employ a registered solar engineer (who has lived off grid) with the experience to correctly design your system.
Note: Because you will be relying on your system day in and day out as your only energy source, it pays to purchase quality equipment. There are cheap off grid systems on the market however, the size and quality of the inverter-charger and the battery is usually where the compromises are made. There is a direct relationship between system cost and long reliable service life. This goes hand in hand with the quality of after-sales service. If you choose a quality installer with years of experience you will benefit from a reliable electricity supply that does not fail in winter when you need it most.
What does off grid solar cost?
For normal sized homes the costs (fully installed) typically start from:
Small house $35 - $50,000
Medium house $50 - $70,000
Large house $70,000 +
A generator is also required. This can be integrated into the system with auto-start functionality so that it seamlessly provides power if there has been too much cloud or to boost the power that is available from the batteries for running large loads. You should allow from $6-14,000 for a quality auto-start generator.
Do you live on a lifestyle property in a rural location?
If you live rurally and want solar, your best option is still the same as most urban dwellers, i.e. a grid-connected solar system. However rural dwellers usually get more power cuts than city dwellers, so adding a generator connection or some batteries is worth thinking about. McNae Group is a specialist in generator integration, battery selection and hybrid solar so make sure you talk to us.
The cost of going off grid
There is a significant set-up cost to being completely self-sufficient on solar and this is something you need to be aware of. The average grid-connected house in New Zealand uses 20-25 kWh of power per day. To provide this much power from an off grid system would cost well over $100,000 – making it too expensive for most people. However, we can demonstrate ways to reduce your daily power usage to around 5-15 kWh per day making off grid solar cost-effective and a very satisfying way to live. Once your daily power demand is reduced the installed price for off grid solar usually ranges in price from $25,000 – $70,000. It's still triple the cost of grid-connected solar but once it’s installed you'll have complete self-sufficiency and no reliance at all on the grid.