{"id":38138,"date":"2020-03-30T15:29:03","date_gmt":"2020-03-30T04:59:03","guid":{"rendered":"https:\/\/www.solarquotes.com.au\/blog\/?p=38138"},"modified":"2025-01-02T07:03:51","modified_gmt":"2025-01-01T21:33:51","slug":"panel-optimisers-danish-study","status":"publish","type":"post","link":"https:\/\/www.solarquotes.com.au\/blog\/panel-optimisers-danish-study\/","title":{"rendered":"Danish Study Shows Solar Panel Optimisers Aren’t Always Optimal"},"content":{"rendered":"
\"Danish

Have solar panel optimiser manufacturers been too optimistic in their performance claims? A Danish study says optimisers can be the opposite of optimal.<\/p><\/div>\n

Solar systems hate shade.\u00a0 They really do.\u00a0 Sometimes they talk to me in my dreams and it’s always their number one complaint, right after being pooped on by birds.\u00a0 But these two problems are related — they hate bird poop because it shades their solar cells.<\/p>\n

A common solution to reduce the effects of shade is to put optimisers on solar panels.\u00a0 These are little boxes of electronics that ensure the current provided by the panel is always optimal for maximising energy output.\u00a0 While this won’t do anything to make up for the reduction in light caused by shade, they can prevent one shaded panel from dragging down the performance of other panels on the same electrical cable, which is called a string<\/a>.<\/p>\n

It is possible to place optimizers only on panels that will be regularly shaded.\u00a0 This helps keep costs and energy losses low and allows them to be a cost effective way to reduce the effects of shade, making them a useful tool for solar system designers and installers.\u00a0 But I don’t recommend using them on solar panels that only suffer from minor shading or no shade at all.<\/p>\n

In the past I would have said it is a waste of money. They aren’t cheap and these days can cost half as much as the panel they’re attached to before including the cost of installation.\u00a0 So I would have said you would be spending a lot of money for little or no benefit.\u00a0 But I may have been going a little easy on them, as a recently published Danish study<\/a> says that, for an unshaded solar array, optimisers are worse than useless and will reduce overall solar output.<\/p>\n

The study comes down pretty hard on optimisers.\u00a0 Its summary states:<\/p>\n

\"Solar<\/p>\n

While there were situations in which optimisers helped, the study found when a 14-panel array received shade from a single thick wooden pole, there was no overall benefit provided.\u00a0 This pole did not provide the heavy shading that can allow optimisers to boost output, but does suggest they are not worthwhile for reducing the effects of light to moderate shade.\u00a0 Another interesting result was optimisers could be less useful for countering the effects of shade from objects in countries that are sunnier than Denmark.\u00a0 Australia is definitely one of these.<\/p>\n

A Danish Study<\/h2>\n

The study\u00a0 was called “Impact of Optimizers for PV-Modules<\/a>“.\u00a0 It was published by SDU — the Universtity of Southern Denmark<\/a> — and the author was Toke Franke<\/a>.\u00a0 I wasn’t able to find much about him except that he’s been involved in writing enough papers<\/a> to make him a PV research publishing powerhouse.\u00a0 I did discover his full name is Wulf-Toke Franke, which I presume is the Danish equivalent of being called Dingo-Toke Franke, so I wouldn’t mess with him.<\/p>\n

Note his name is Toke and not Toki, so he has nothing to do with the Danish musician Toki<\/a>.\u00a0 At least, I assume he doesn’t.\u00a0 For all I know, they could be brothers.\u00a0 It would be just like Danish parents to name one kid Toke and the other Toki and expect everyone to keep them straight.<\/p>\n

\"\"

Danish musician Toki speaking his native tongue.<\/p><\/div>\n

3 Systems Were Tested<\/h2>\n

The study used a set of 42 solar panels located on a small European peninsula packed full of Vikings and dairy cows called Denmark:<\/p>\n

\"Solar

The picture on the left is the actual test site in Denmark. The picture on the right is the test site after it has been Southern Hemisphere adjusted.<\/p><\/div>\n

Testing was conducted over a year.\u00a0 Because at some times of year solar panels were shaded by Danish vegetation, after 5:22 pm testing was always stopped at this time to ensure comparable results.\u00a0 The 42 panels consisted of three strings of 14 fitted with the following hardware:<\/p>\n