Solar PV Inverters

I’ve noted that Choice puts a lot of smart effort into assessing fridges. This includes energy efficiency, thermal performance, storage efficiency etc against the makers claims/specification.

It would seem many of the same elements including environmental testing in a heated room such as that used for aircons might be equally usable for comparing inverter manufactures claims.

It appears that there is no independent testing of product performance aside from electrical safety standards?

With inverters costing from less than $1,000 to several thousands, would it be useful for Choice to backup the buying guides with some real performance tests?

Firstly to demonstrate which products claims are honest.

Secondly to identify which products may perform better under Australian conditions.

Perhaps (other than perceived reliability) a cheap inverter does the job 99% as well as a top end brand?

The current option is to purchase purely on reputation and size of the manufacturer/support. Not all expensive brands have been without major problems. Support is a moving target?

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Great suggestion.

The inverter evaluation would complement the work done with the solar PV panels.

Another question I would add: is there any difference between solar & wind inverters; and are there any inverters capable off handling input from both sources simultaneously?

If we want to go further, what about wind turbines? There are lots of designs & forms out there. Are any of them usable in an urban environment to augment or be an alternative to solar generation

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Choice already has relationships with capable companies who might be able to provide such information.

Considering the budget required to purchase and deploy PV arrays for such testing how many higher volume, ‘closer to our more common purchases’ might have to be foregone by bringing it in-house?

With PV panels and inverters reliability as well as performance are equally important. What would league tables actually tell us as consumers?

Not what was asked for, but excellent guidance in its own right, here. Pick your inverter from the alpha list at the bottom of that page.

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Choice has already indirectly done some assessments on inverters used for"

It wouldn’t be hard for Choice or its testing associates to prepare a summary of their findings of some of the inverters trialled under the above test conditions.

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There’s Buckley’s chance of any local council allowing wind turbines in urban or adjoining urban areas, far too many people would object. However, that isn’t really a problem because, for the dollar spent, in almost every location in which people live, a PV system will produce more output. This is especially the case in urban areas, as the air is very turbulent due to buildings and trees, but wind turbines work best in non-turbulent air, and are more prone to failure in turbulent air due to high induced stress on the turbine.

For a domestic scale wind turbine to be effective financially and in energy output, it needs to be situated at least 10m above obstructions within 100m, and needs to be located in an unpleasantly windy location that is frequently cloudy. Many small wind turbines up to 1-2kW output need consistent ~40km/hr wind speed to operate near their power rating. Some of the micro-turbines as used on boats (~50W) need 45-50km/hr.

Wind turbine grid-connect inverters do exist, although the available range is extremely limited.

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6 posts were merged into an existing topic: Wind Powered Energy Generation

Perhaps, if indeed there are any trials that actually test the inverters against specification.

I’d suggest

Testing at CHOICE

And how to book a lab tour

From washing machines and steam mops, to coffee grinders, laptops, TVs and health insurance – there aren’t many products or services that haven’t been put through our independent tests. We test so we can bring you the best unbiased advice on what to buy.

The challenge is for Choice to live up to it’s motto, “We test”.

It’s worth taking on board,

There is an assumption here that the testing will be expensive relative to the benefit or outcome. Rather than speculate it needs the Choice testing team and any outside interested parties to look at what is reasonably necessary. And base any decision on an informed view.

Solar PV will only continue to grow. And unlike so many other major house hold purchase Choice does not make a clear recommendation on a brand and or models, as it does for fridges, washing machines or air conditioners.

The industry leaves it to the market genius of each retailer to push their preferred products, or the consumer to make a call based that steers towards past reputation and the most expensive products. For any other product Choice would be identifying the value products and sorting the second rate from the performers. Expensive is not always best.

And most importantly Choice tests all products against real everyday Australian conditions. They are not rubber stamped against a European laboratory at 20C.

P.S. Alternatively
If the CEC actually performance tests each approved inverter against all specifications including load and temperature performance, perhaps Choice could encourage the CEC to share the details of what is tested, how and the individual results.

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Hi all. A review of solar inverters is definitely on our radar, and if we can pull it off, it will almost certainly be along the lines of using a partner organisation as has been suggested. It’s not feasible to use our current lab facilities (e.g. our thermal testing rooms used in fridge tests) due to the wiring/power supply requirements for inverters, among other things. They can’t just be plugged into a regular power point, after all, but usually need a DC power input to simulate power feed from solar panels. We haven’t yet got a solution but I’m hoping we’ll at least have a planned way forward within the next few months.

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That’s wonderful to hear.

It would also be useful if at the same time you included the vendor supplied household monitoring as part of the testing and assessment.

In particular what happens when the internet connection fails. In our situation, the wifi connection between the inverter and guest network we set up for the inverter does not always reconnect without intervention. Cynically the inverter wifi dongle offers it’s own network as well as trying to reconnect to any other likely host, despite not having suitable credentials. It seems very eager to reconnect to the cloud server, (which may be encouraging), but not very bright in doing so. Or is it, which may be more alarming than reassuring?

Some inverters only have a wifi option. Others provide ethernet cabled connection and some a dedicated connection using modbus. The last listed usually requires appropriate software from the inverter vendor.

Importantly, any grid connected inverter monitoring of included in the marketing needs to be reliable, easily accessed and effective. Most of the online product reviews I have seen of inverter products never say a bad thing about the monitoring. It’s as though the reviewers have never used the products!

If Choice does proceed, perhaps it could develop a standard questionnaire for interested members to respond to. Across all there should be some good feedback on how many use or do not use the monitoring, and what benefits/problems exist with different products?

P.S.
We are currently having internet and phone line issues ADSL2 service. Telstra copper line? If this was not happening every hour, it might not be so obvious, as on other occasions the system reconnects reliably over night.

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