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View Full Version : Anyone know anything about PV Solar Enhancers?


MadsDad
28th Jul 2016, 11:24
Just had someone trying to sell me a PV Solar Enhancer. This device is meant to increase the registered generation from our solar array by up to 20%. The thing is I don't understand how it is supposed to work at all.

As I understand solar stuff after the panels generate the DC power there is an inverter which converts the DC to AC to match the house supply. The thing is, again from a low knowledge base, I understood that the inverter output would be AC which matches the voltage and phasing of the mains supply. The sales stuff for the enhancer says that the inverter output would actually be some 4 volts greater than the mains supply so as to 'push' the solar electric into the house and so this would be used in preference to the lower voltage mains (I can understand that bit).

The inverter will apparently cut out if the voltage exceeds 250 and the enhancer reduces the chances of this, I think. But our system doesn't appear to be cutting out anyway. Anyone know anything about these devices?

ShyTorque
28th Jul 2016, 13:15
They probably need to be lubricated every day with snake oil.

I'd rather have an energy storage system so that the panels still work in the event of a power cut (most "current" domestic systems don't, including mine).

Kulverstukas
28th Jul 2016, 13:29
the whole concept of

to 'push' the solar electric into the house

makes me wonder

G0ULI
28th Jul 2016, 13:29
The designer of your current system has spent considable time and effort ensuring that the system components are matched and comply with whatever regulations are applicable for safety and connection to the public grid.

The salesman wants you to connect an untested, one size fits all device, that will improve the efficiency of your system by up to 20%.

Avoid at all costs. The device will not work. At best it will skew the voltage and current relationships to try and fool the monitoring devices into registering more power than is actually being generated. It will actually reduce the efficiency of your system and may well invalidate any guarantees or safety certificates you have.

Sallyann1234
28th Jul 2016, 13:53
I wouldn't touch anything like that with a double-insulated barge pole.

De_flieger
28th Jul 2016, 13:55
Sounds very scammy. I had a look online and the first website I could find selling this product was very vague about how it actually works, but certain that it could be retrofitted to all types of solar setups. Their claims dont seem to make sense, as any reasonable inverter is more than just a basic inverter. The setup will have fairly clever voltage regulators and converters built into it, so adding an extra set of transformers or converters between the panels and inverter (or inverter and house power? The website wasnt clear to me) will introduce a set of extra conversion losses and potential problems. If a simple box could get an extra 20% output from the panels, they'd all come with the box already fitted :)

As a previous poster suggested, it probably requires topping off with high grade snake oil on a regular basis.

rans6andrew
28th Jul 2016, 14:19
We have been plagued by calls from people trying to sell us something similar. When you cut through the hype mostly they are actually trying to sell you a very expensive battery to store much of the electricity that you currently push back up the grid. Being of a scientific bent and careful with my hard earned I immediately want to know 3 things, what is the total amount of energy that the system will store?, how fast can it be liberated for my domestic use? and how much does it cost to install?

Sometimes they can tell me how much energy can be stored but they don't understand Q2 and don't know the answer to Q3 (or won't tell me). Chivvying them along a bit suggests a lot more than 10 000 to store maybe 10KWH. SOME days of the year my system makes 20KWH but for more than half the year it is much less than that. The solar system we have, with a good feed in tariff, makes about 50% more revenue annually than our electricity bills cost us. To invest upwards of 10 000 in a system which, at best, will reduce our bills to zero, just doesn't add up. That is assuming that the storage battery lasts for the 20 years remaining on our FIT contract, which I doubt.

We just need to maximise our usage when the sun is actually shining. Cook, run washing machine, heat hot water, use bread maker, charge laptop batteries etc and then use efficient lighting when it gets dark. I might put the house lighting onto an inverter powered from a leisure battery arranged to charge during the daylight hours. This will make us semi immune to power cuts in the evening/night so I can read my paper in peace.

MadsDad
28th Jul 2016, 16:13
Thank you for your responses, lady and gentlemen. Much appreciated.

It tends to accord with my own opinion. One thing I didn't originally mention is the salesman also mentioned the posibility of purchasing a battery storage unit. This would come in at about 4,500 for 7 Kwh and not particularly cost effective as far as I can tell.

Ok, keep looking for the pot of gold elsewhere.

G-CPTN
28th Jul 2016, 16:24
On a slight thread drift, I was offered the opportunity to become a (self-employed) salesman selling energy conservation systems for domestic heating systems.

What it amounted to was adding room thermostats to a 'computer' which could be programmed to different limits (so that unoccupied rooms were not heated or different temperatures could be applied at different times of day and on different days).
The 'mark-up' on the components was outrageous and the home-owner (and the salesman) were paying through the nose for the minimal benefit that they would ultimately achieve.

I didn't accept the offer, so I never knew knew whether the (exaggerated?) claims for the projected 'savings' were justified.

Cazalet33
28th Jul 2016, 17:35
Pv systems produce power. You do not increase the amount of power produced by changing the voltage. If you increase the voltage, then you reduce the current. No change to the power, other than a slight reduction caused by the heat loss in the conversion.

Snake oil. Avoid.

llondel
28th Jul 2016, 19:51
There are several configurations of solar systems.

The simplest method just sticks a bunch of panels in series and hangs some electronics on the end to convert the output to something useful. Downside is that you're limited by the poorest-performing panel and if one fails, you get zero output. If there's a partial shadow or uneven lighting then the performance of the whole string is affected.

The other end of the scale is the micro inverter system, where each panel has its own dedicated electronics that converts it to something useful and they're all effectively wired in parallel. This obviously costs more but each panel is independent and if one fails then the rest keep working and producing useful output.

In between is the series string with conditioners, where there is (presumably cheaper) electronics attached to each panel in the string that can compensate for panels in shade or failing.

It is possible that the enhancers are this third method, but I'd still get them checked for snake oil content before paying any money.

llondel
28th Jul 2016, 19:54
What it amounted to was adding room thermostats to a 'computer' which could be programmed to different limits (so that unoccupied rooms were not heated or different temperatures could be applied at different times of day and on different days).

This only works when you keep doors closed. Those of us with cats know that this is not possible, because a cat will always need to have the door opened so it can decide whether to be on the other side. If the doors are open you can't not heat some of the rooms.

Sallyann1234
28th Jul 2016, 21:38
The answer to that is simple. Kick out the cat/s and close the doors. They are a total waste of energy anyway.

david1300
29th Jul 2016, 00:50
Does it come with a "but wait, there's more" device that you can add to your fuel tank to make your car more economical? ;)

david1300
29th Jul 2016, 00:57
....We just need to maximise our usage when the sun is actually shining. Cook, run washing machine, heat hot water, use bread maker, charge laptop batteries etc and then use efficient lighting when it gets dark...

Shirley, this is the wrong way round :8. During the day when we are generating power we sell it to 'the system' at the feed in tariff of 50c and then at night we buy it back at 28c (figures are from memory). So it's best to minimise your usage when the sun is shining, in the day thereby selling the maximum you can at the higher FiT.

yotty
29th Jul 2016, 07:59
Link to the Microgen Database / General discussion / 25% more Output from Inverter Rewiring, Too Good to be True ? (http://www.microgen-database.org.uk/forum/topic/3447/)

andytug
29th Jul 2016, 08:59
Anything advertised claiming to save /enhance/add/whatever "up to" a percentage is going to be lies.
See also " up to" 24MB broadband, "up to" 56Mbps wireless router, etc etc. Weasel words never bode well and you will not get that saving, if that figure's ever been achieved it'll have been in a lab under extremely controlled conditions with well matched components. In the real world you'll be lucky to get half, probably damage your system and invalidate any guarantee on it (there will be a clause preventing modifications I would be almost sure). Avoid.

Avtrician
29th Jul 2016, 10:01
It sounds like rubbish to me. Its the maths.....
5 x 50 volt panels (1 amp for argument sake) placed in series will give 250 Volts, capable of supplying 1 Amp (250 watts). when connected to a 1 to 1 inverter will give ( its a 100percent efficient system) 250 volts AC supplying 1 amp (250 watts).
If the 5 panels are placed in parallel, you would have a 50 volt supply capable of 5 amps (oh look, that = 250 watts). Now connect it to a super efficient 1 to 5 inverter, you would have an output of 250 volts AC capable of supplying 1 amp....

You cant get 25% more from a system thats at 100%

419
29th Jul 2016, 11:10
david1300
Shirley, this is the wrong way round . During the day when we are generating power we sell it to 'the system' at the feed in tariff of 50c and then at night we buy it back at 28c (figures are from memory). So it's best to minimise your usage when the sun is shining, in the day thereby selling the maximum you can at the higher FiT.

In the UK, the money received from exporting power back to the National grid is not very much at all and exported power is normally estimated. (most homes with a solar PV system don't have a separate export meter).

If my system produces 25Kwh during the day, I get paid about 18p for every Kwh produced and I can use all of this power without being charged for it.
For export purposes, it is estimated that 50% of the power produced is exported and for this, I received about 7p for every Kwh.

Because of this, it makes sense to maximise your electricity usage during sunny days when the system is producing lots of power as you are getting paid to produce it but you don't get charged for using it and even if you use 100% of the generated power, you still receive the payment for the estimated 50% that you have exported.

Sallyann1234
29th Jul 2016, 11:45
Because of this, it makes sense to maximise your electricity usage during sunny days when the system is producing lots of power as you are getting paid to produce it but you don't get charged for using it and even if you use 100% of the generated power, you still receive the payment for the estimated 50% that you have exported.
And that in a nutshell is why subsidies for domestic 'renewables' are crazy and should be stopped ASAP. :ugh:

Avtrician
29th Jul 2016, 11:59
In Oz, there is a meter that records the amount of electricity sent to the grid ( in domestic installations) unless it goes straight into the un- metered side .; in that situation the meter can go backwards, so reducing your bill.

late-joiner
29th Jul 2016, 12:33
In the UK you benefit from solar 3 ways domestic level:
- you get paid the feed in tariff for what you generate, which is measured, whether you use it or export it.
- you get paid for 'deemed' export at the export tariff, the assumption being you export half of what you generate.
- you avoid having to purchase whatever you use that you generate yourself.

So here it is always beneficial to maximise self-consumption.

If your meter does go backwards when you export then you are meant to report it and have it changed. Mechanical meters here have had a ratchet for I think 30/40 years to stop them going backwards. Electronic meters are programmed not to.