What’s All the Hype About Plug-In Solar, AKA Balcony Solar?
By Aniket Bhor on in New Solar Technology
New Zealanders are largely in favour of solar energy. Surveys show that a huge proportion of Kiwis see solar panels as a good choice. And yet, less than 4% of the country’s homes have solar panels on them. Why?
Different families have different reasons for not going solar, but the main reasons usually are these:
- Rented homes.
- Apartments where the rooftop is shared.
- Financial readiness.
- Roofs unsuitable for solar panels.
However, all of this is about to change, thanks to Plug-in solar, aka Balcony solar. Let’s see what that is, and how it can be a game-changer for so many of us.
What is Plug-in Solar?
Plug-in solar is a mini solar power system, involving one or two solar modules, a microinverter, and occasionally a battery. The whole unit has a domestic ‘plug’ that you can insert into your wall socket to power your home’s appliances.
Also sometimes called balcony solar (since that is where it’s typically installed), plug-in solar eliminates the complexity of installing a full-fledged solar power system, which involves complicated racking and wiring, not to mention the bureaucratic hassle of getting a system approved.
A typical plug-in solar unit can be anywhere between 400 and 1200 W. It usually includes a sub-1000 W inverter and a simple, DIY installation kit with mounting brackets. Below is an example balcony solar unit, offered by EcoFlow, one of the leaders in the plug-in arena.
A typical plug-in solar unit (source: EcoFlow)
Despite the name, balcony solar doesn’t necessarily have to go onto a balcony. If you have a shade-free backyard, you can simply put the panels on the ground, similar to the image above.
Naturally, plug-in solar cannot do everything that a traditional solar power system does, notably running power-hungry devices like air conditioners. In markets where plug-in solar is legal, the inverter output is capped (e.g., 800 W in Germany).
They are also only capable of saving a fraction of the money that a rooftop system saves. Nevertheless, the advantages of plug-in solar typically outweigh its limitations, as we’ll see in the next section.
The Advantages of Plug-in Solar
Low Cost
Plug-in Solar is to rooftop solar what electric bikes are to cars. They offer a smaller and less powerful entry point to energy independence, bridging the gap between no solar and rooftop solar. Priced around $3,000 or lower, a balcony solar system costs about 25% of a full-fledged rooftop system.
What’s more interesting, however, is the cost per watt of balcony solar. While it may intuitively feel like a smaller system costs more per watt, plug-in solar units are actually cheaper, since they eliminate labour costs.
Plug-in solar has a higher material cost but lower overall costs. To put this in context, a typical plug-in solar power system may cost around $1.8/W, while rooftop systems cost $2.04/W (more for smaller systems).
Since lower-income households spend disproportionately more of their income on electricity costs, plug-in solar makes an excellent case for those who are especially unable to afford rooftop solar.
Strong Returns on Investment
The low cost per watt of plug-in solar translates to strong returns on investment. For instance, an 800 W, $1,500 system may generate around 1,000 kWh of energy in a year. Given New Zealand’s average electricity cost of 40 cents/kWh, you could save $250 - $400 per year, depending on how much of the solar energy you use. This means your system would be paid back in 4 to 6 years.
Quick to Install
Installing a plug-in solar system is faster than installing a rooftop solar system, especially since there is no paperwork involved. However, it will not match the installation quality and optimized performance of a rooftop system.
Suitable for Outliers
As mentioned earlier, plug-in solar is suitable for homes that cannot get rooftop solar, like apartments, or in some cases, houses with bad roofs. It is also a good substitute for rooftop solar where homes face strict land covenants or body corporate rules.
Portable
At risk of stating the obvious, the portability of plug-in solar systems makes them significantly more desirable than rooftop systems if you plan to change homes. This is especially true for families or individuals who live in rented homes. With about a third of Kiwis living in rented homes, this may be a big selling point for plug-in solar.
Balcony solar not only allows you to take it along when changing homes, but also to change its position or location in the same home as the sun changes its trajectory through the sky.
Plug-In Solar in New Zealand
Despite the positive outlook, plug-in solar is legal in very few countries. This has to do mainly with existing regulations that need amendments. Here in New Zealand, WorkSafe banned plug-in grid-tie inverters via a formal prohibition notice effective January 12, 2012.
The purpose of this rule was to avoid power flowing back into the grid through the inverter and potentially harming technicians working on the grid equipment. It made sense at the time, but all inverters now come with an islanding protection mechanism, which shuts them down as soon as the grid power turns off. All that remains now is to amend the WorkSafe prohibition and create a proper framework to allow plug-in systems.
The good news is that both the Labour and National parties are now promising to amend the regulations and make plug-in solar accessible. And if things go well, we might even find balcony solar subsidised. Check out our piece about how solar is now an election issue – something we hope becomes a very normal thing both here and worldwide.
This is not all. Recently, the Ministry for Regulation completed a sector review into residential solar installation, aiming to ‘make New Zealand the simplest place in the developed world to install solar.’ The review makes seven recommendations with the above aim, and one of these seven is ‘legalising plug-in solar in New Zealand’.
In all likelihood, plug-in solar will see roaring success once legalised, as it has done in other countries. Germany, for example, had installed 1 million plug-in solar systems in 2024, and now reportedly has around 3-4 million systems generating power.
New Zealand easily outperforms Germany in terms of solar potential. And while its solar adoption may not have been as remarkable as Germany, balcony solar might just be the thing that gets New Zealand the kind of acceleration in solar energy that Germany saw.
Possible Plug-in Solar Product Options
If things go as expected, we may see a plug-in solar-related regulation in place within the next year or so. And like all technologies, we will already have product options ready.
One of the players gearing up for the market to kickstart is Xinpuguang Solar. It already has a fleet of what it calls ‘Balcony Power Plants’ for sale on its website. Xinpuguang uses its own equipment in the offered systems, and prices them attractively. The brand offers panels from 300 W to 1200 W, and even has a variety of off-grid, flexible solar kits for sale.
Xinpuguang Solar 600 W balcony solar kit
Aside from that, existing market leaders in established markets will obviously enter New Zealand and create a strong presence. Two of these are EcoFlow and Anker. Both brands are among the bestselling options in Germany and the UK, two places where plug-in solar is legal and fast-growing.
Both EcoFlow and Anker have held a solid presence in small solar kits, whether grid-tied or off-grid. Their products are more tried and tested, offer more features and reliability, and perhaps also better customer support.
Final Thoughts
Plug-in Solar can be compared to electric mobility in the sense that its future is inevitably bright. The regulatory hurdles holding it back are minor and temporary, and once available, we expect it to sell rapidly.
As for the question of whether you should buy plug-in solar, it depends on whether you are able to also install a rooftop system. Plug-in solar can in no way match the scale of savings that rooftop solar (or even ground-mounted solar) can offer. If you are able to get a full system, we recommend installing it and enjoying substantial, long-term savings.
But if you’re not able to install a full-blown solar power system, plug-in solar is certainly way better than not having any solar panels at all. Kristy, Founder of My Solar Quotes, sums everything up quite nicely. Here are her thoughts on plug-in solar and its usability:
“I am pleased to see balcony solar becoming legal in New Zealand, particularly because it opens up solar to renters. However, I see it as a much more limited option compared with a conventional rooftop solar system. I personally think balcony, or plug-in, solar is quite limited in what it can achieve.
A 1kW system simply isn’t going to make a huge difference to a household’s power bill. Where I do see real value is that it gives renters, who have largely been locked out of solar, an opportunity to generate some of their own power.
Potentially even more useful is the resilience side. With the right system, people could still generate and use stored power during an outage - enough to keep phones and other communication devices charged, help keep a fridge cold, and run a few lights during a severe weather event.
My concern is that consumers may find the options confusing, particularly without an experienced solar installer guiding them. If New Zealand follows similar electrical safety requirements to countries such as Germany, many standard balcony solar and battery systems will still need to shut down during a grid outage.
Consumers specifically wanting backup power will need to choose a system designed for that purpose, such as Enphase’s IQ Balcony Solar System with its dual-mode capability. Essentially, that allows the system to switch into off-grid mode during an outage - and to me, having access to power when the grid is down is potentially far more valuable than shaving a couple of hundred dollars off a household’s annual power bill."