GRID TIE INVERTER EN 50438

martin3757

CAN ANYBODY HELP PLEASE , I AM THINKING ABOUT GOING ON GRID WITH A 2KW WIND TURBINE , THERE ARE MANY INVERTERS ON EBAY BUT NONE SEEM TO HAVE THE EN 50438 STANDARD . I HAVE SEEN EN 50438 PV INVERTERS ADVERTISED , BUT CAN THEY BE USED FOR TURBINES . I BELIEVE THAT THIS IS THE ONLY STANDARD THE ESB ACCEPTS , ANY HELP AND POINTERS PLEASE

quentingargan

martin3757 wrote: »

CAN ANYBODY HELP PLEASE , I AM THINKING ABOUT GOING ON GRID WITH A 2KW WIND TURBINE , THERE ARE MANY INVERTERS ON EBAY BUT NONE SEEM TO HAVE THE EN 50438 STANDARD . I HAVE SEEN EN 50438 PV INVERTERS ADVERTISED , BUT CAN THEY BE USED FOR TURBINES . I BELIEVE THAT THIS IS THE ONLY STANDARD THE ESB ACCEPTS , ANY HELP AND POINTERS PLEASE

I only know of two types of wind inverter that can be used in Ireland under the new EN50438 standard, and this is likely to remain the case because the ESB demands a unique standard for Ireland, which must be certified. Since there are only about 400 domestic turbines in the country, the two companies who have certified their products are unlikely to recoup the certification costs in the short term...

I will PM you details. Q

Jim Martin

Don't know if this is any help (see page 21), good for UK mains connection but only for a 1kw turbine:

http://www.futurenergy.co.uk/pdf_doc/TurbineGuide.pdf

quentingargan

Jim Martin wrote: »

Don't know if this is any help (see page 21), good for UK mains connection but only for a 1kw turbine:

Unfortunately that inverter isn't produced to EN50438. The unique Irish grid standard appears to be a spanner that someone in ESB threw into the works, because the grid itself doesn't meet the same standard,

But unless you can give ESB the serial number of an EN inverter, and a cert to show that it meets the unique Irish grid standards, they won't consent to the connection, and more importantly, they won't pay you for electricity you export.

martin3757

thanks for all replies , has anyone heard of vde 0126.1.1 standard it may be a german standard that is compliant with en 50438 have a look
http://www.solar-inverter.com/eu/en/download/Manual_Solivia_5.0_EU_G3_all_languages_web_DataId_633495_Version_5.pdf

quentingargan

martin3757 wrote: »

thanks for all replies , has anyone heard of vde 0126.1.1 standard it may be a german standard that is compliant with en 50438 have a look
http://www.solar-inverter.com/eu/en/download/Manual_Solivia_5.0_EU_G3_all_languages_web_DataId_633495_Version_5.pdf

Similar to en50438. But doesn't have Irish variations to en in relation to voltage and frequency ranges so cannot be used here I'm afraid.

air

This whole issue is a total joke and reflects very poorly on the ESB.
Why can't they conform to a common European standard in this regard?
This is no different than if the ESB decided that electrical appliances used in Ireland have to conform to some enhanced standard they have made up. It achieves nothing other than increasing costs for Irish consumers and drastically reducing the level of choice in the market place.
Incidentally Quentin, do you mind sharing the two inverters?
Windy Boy 2500 and Aurora 3600 perhaps?

quentingargan

air wrote: »

This whole issue is a total joke and reflects very poorly on the ESB.
Why can't they conform to a common European standard in this regard?
This is no different than if the ESB decided that electrical appliances used in Ireland have to conform to some enhanced standard they have made up. It achieves nothing other than increasing costs for Irish consumers and drastically reducing the level of choice in the market place.
Incidentally Quentin, do you mind sharing the two inverters?
Windy Boy 2500 and Aurora 3600 perhaps?

Agree about ESB. Completely daft. And the problem is that their own grid doesn't conform to the standard demanded of them by microgenerators, so if the grid goes up to 253V, our inverters have to shut down. We regularly see the grid operting above this level.

Air - I'm not sure what you mean by "do I mind sharing the two inverters". Do you mean the names of those that have EN conformity? For wind, it is SMA and Aurora. For solar it is SMA and Fronius as far as I know at present.

323

Also agree about ESB, blatently obvious they do not want grid connected micro generation.

Also unsure what you mean by sharing two inverters. Unsure but it's most unlikely that you could connect both the to same main power panel.

Don't want to throw a spanner in the works but my question is, Why go grid tie?

Grid-tie makes perfect sense anywhere but Ireland, as you will only get a pathetic 10 cent kWh for what you export, then pay more than twice that for what you use from the grid.
To make a system cost effective I would want all produced power going to local (downstream AC) loads with any excess being diverted to first battery top-up (UPS), then to a secondary load, domestic water heat. Thereby offsetting full price oil/gas used or electric power imported from the grid later at full cost.

quentingargan

323 wrote: »

Don't want to throw a spanner in the works but my question is, Why go grid tie?

Grid-tie makes perfect sense anywhere but Ireland, as you will only get a pathetic 10 cent kWh for what you export, then pay more than twice that for what you use from the grid.

To make a system cost effective I would want all produced power going to local (downstream AC) loads with any excess being diverted to first battery top-up (UPS), then to a secondary load, domestic water heat. Thereby offsetting full price oil/gas used or electric power imported from the grid later at full cost.

Generally an oil fired system will provide heat for about 8c per Kw Hr, so any electricity you export at 10c is making you a profit on that option. Also, you may not necessarily want heat at the time when you have wind. Hot water cylinders get hot very quickly, and soon you have radiators heated at night when you don't really need it.

The other approach is battery storage and becoming self-sufficient, which I have done at home for about 8 years now. Occasionally we need to top up the batteries, and we can do that at night on the off-peak rate.

However, you need to bear in mind that on a day of good wind, your batteries will fill very quickly, after which you are back to using electricity for heat that you may or may not want.

There is also the cost of cycling batteries. The best ones will do about 3,000 cycles if you look after them really well. Most households would need about 20KwHrs for a reasonable degree of cover in calm periods, but even cutting that in half, if you opt to have, say, 10 Kw Hrs of storage, and you cycle down to 50% depth of discharge (the most economical option) you will need 20KwHrs of batteries, or just over 6 250Ah 12V batteries at a cost of about €2,800 for proper renewable energy batteries. That gives you 3000*10 Kw Hrs, costing about 9c per Kw Hr to cycle your batteries.

To my mind, grid tie is still the most economical way of transmitting power produced locally. We put in our off-grid system at a time when the ESB was paying nothing for power exported (they use to call it "spilling").

freddyuk

quentingargan wrote: »

Agree about ESB. Completely daft. And the problem is that their own grid doesn't conform to the standard demanded of them by microgenerators, so if the grid goes up to 253V, our inverters have to shut down. We regularly see the grid operting above this level.

Air - I'm not sure what you mean by "do I mind sharing the two inverters". Do you mean the names of those that have EN conformity? For wind, it is SMA and Aurora. For solar it is SMA and Fronius as far as I know at present.

There is another EN50438 full compliant Irish inverter which I own the rights to so PM me if interested. It is a Solar inverter 2.5kw/3kw or 3.8kw.
Not a lot of use soon as the incentives are being scrapped but I hope to get mine connected before the deadline as anything is better than nothing.

stenB

Hi FreddyUK !
Please advise position with this PV inverter today, 2013 !
Rgds Sten

stenB

Hi quentingargan.
I cannot consolidate 20 KwH with 6250 Ah at 12 V.

To simplify: 100Ah at 12 V is 1200 Watt for 1 hour or 1.2 Kwh
or 1 Kwh = 83 Ah at 12v. Giving 20 kWh <= 1700 Ah .
I don't know what batteries are most economical but it would be 17 100 Ah batteries. At 200 Euro each (deep cycle) it would be 3,400 Euro today.
The "deep cycle battery" can probably go down below 50%, how much ?

Please confirm or advise the Kw/Ah part!
Sten

quentingargan

stenB wrote: »

Hi quentingargan.
I cannot consolidate 20 KwH with 6250 Ah at 12 V.

To simplify: 100Ah at 12 V is 1200 Watt for 1 hour or 1.2 Kwh
or 1 Kwh = 83 Ah at 12v. Giving 20 kWh <= 1700 Ah .
I don't know what batteries are most economical but it would be 17 100 Ah batteries. At 200 Euro each (deep cycle) it would be 3,400 Euro today.
The "deep cycle battery" can probably go down below 50%, how much ?

Please confirm or advise the Kw/Ah part!
Sten

There was a space between the 6 and the 250. Shorthand and a bit approximate too.. sorry. So it is 6 off 250Ah or 1500Ah. That would make 18KwHrs and at 50% depth of discharge you are down to 9kw hrs per day.

A 6,250 Ah battery pack would keep things going for a bit!!

quentingargan

stenB wrote: »

The "deep cycle battery" can probably go down below 50%, how much ?
Sten

Batteries have a chart for number of cycles -vs-depth of discharge. I just came across the attached which shows what your're looking for in relation to Victron batteries as an example Q

stenB

Interesting data. I read from it that for a gel type battery 300 % more power can be taken out with 30% discharge cycle compared to a deeper one taking out 80% of battery power.
Same increase is only 31% for the gel deep cycle.But the overall output seems to be 3 x more/longer for the gel type. What is the price ratio gel long life/gel deep cycle ?
Thanks for info!
Sten

quentingargan

stenB wrote: »

Interesting data. I read from it that for a gel type battery 300 % more power can be taken out with 30% discharge cycle compared to a deeper one taking out 80% of battery power.
Same increase is only 31% for the gel deep cycle.But the overall output seems to be 3 x more/longer for the gel type. What is the price ratio gel long life/gel deep cycle ?
Thanks for info!
Sten

I think you are misunderstanding that chart. The vertical axis is the number of cycles, irrespective of the size of battery. So a gel long life battery is good for 4500 cycles at 30% discharge depth, 2500 cycles at 50% and 1500 cycles at 20%. So you can buy a small battery and discharge it deeper, and it won't last as long.

Bluefang

Once an invertor complies to EN50438, it does not matter if it is a sunnyboy or a windyboy, this is just branding.
Most invertors are software configurable anyway - if you were to buy one you should be supplied with the software that enables the parameters to be modified for anti-islanding times etc, however the ESB will want to see the type test cert for a particular invertor.

There are sound reasons why ESB insist upon EN50438 compliance - in Ireland we have a nominal mains of 230V. vs 240V in Britain, also the deviation of phase from 50Hz has different tolerances (1% below, 4% above if memory serves me), again these differ from Britain and other countries.

Download the spec from ESB.ie and you will see what I mean.

quentingargan

Bluefang wrote: »

Once an invertor complies to EN50438, it does not matter if it is a sunnyboy or a windyboy, this is just branding.
Most invertors are software configurable anyway - if you were to buy one you should be supplied with the software that enables the parameters to be modified for anti-islanding times etc, however the ESB will want to see the type test cert for a particular invertor.

There are sound reasons why ESB insist upon EN50438 compliance - in Ireland we have a nominal mains of 230V. vs 240V in Britain, also the deviation of phase from 50Hz has different tolerances (1% below, 4% above if memory serves me), again these differ from Britain and other countries.

Download the spec from ESB.ie and you will see what I mean.

Yes - there are reasons for Ireland to have a unique spec, but since the market for solar and wind is so tiny here, and since the grid doesn't even meet this EN standard itself, then the unique Irish standard just becomes an obstacle to supply.

I have spent years trying to persuade inverter manufacturers to certify to the unique Irish standard, but when they ask the volume of sales likely, it is laughable to ask them to go to this trouble. One company has now agreed to these tests, but there is a lot of work involved, and it is all quite preposterous.

The grid here regularly goes above the 253V permitted, and trips the inverters. ESB has told people to unravel the standards on the inverter. It is absurd.

stenB

stenB wrote: »

To simplify: 100Ah at 12 V is 1200 Watt for 1 hour or 1.2 Kwh
or 1 Kwh = 83 Ah at 12v. Giving 20 kWh <= 1700 Ah .

This is a commonly oversimplified formula. Ah ratings are only accurate to the rated discharge curve, ie. the C20 rate which is a full discharge in 20 hours @ 27°C. This is due to internal resistance.

Lead acids display exponential discharge curves. The harder you discharge them the less they give, whereas the gentler you discharge them the more they give.

See here for a more realistic capacity figure.

Peukert calculator: of course you still have to compensate for temperature yourself. Which can half your capacity when it's cold enough.

There is a certain economy in overspec-ing a battery bank. One could conceivably triple one's capacity by doubling your bank size. Provided you are aware of how to run loads accordingly.

stenB

stenB wrote: »

Interesting data. I read from it that for a gel type battery ... the overall output seems to be 3 x more/longer for the gel type.
Sten

The cycle life is more to do with mass and plate composition than the electrolyte type.
Here's information on an open lead acid type that claims ~ 2750 cycles @ 50% discharge.

I don't recommend gel types, they're expensive, liable to failure in the event of minor charging faults, slower to charge and can't be maintained.

Unless you have a desire to turn your batteries upside-down every once in a while they're not worth it imho.

air

Has anyone got an up to date list of EN50438 (Ireland) compliant inverters that are currently available?
There is scant information elsewhere so listing them in this thread may be of use to others.

quentingargan

air wrote: »

Has anyone got an up to date list of EN50438 (Ireland) compliant inverters that are currently available?
There is scant information elsewhere so listing them in this thread may be of use to others.

Up to date? I'm afraid there hasn't been a delute of companies putting their inverters through the certification process since the tariff was reduced from 19c to 9c. So the list hasn't dated.

The only ones I know of are SMA and Power One wind. Power One solar are supposed to be getting certified soon. There are a few other inverters I know of where you can adjust the settings internally to match the Irish grid requirements and Electric Ireland will generally accept a screenclip of the settings.

air

Thanks Quentin. I didn't realise that the tariff had been reduced either.
It really puts a dent in the viability of net metering when the rate paid for generation is so far below that charged for consumption.

That is a positive development at least if they will accept generic units with the correct settings.
It would be great if they could approve this process officially such that manufacturers can then provide generic units for sale across countries which use EN50438 once the correct local settings have been applied.

freddyuk

Steca have approved certificate for PV inverters.

quentingargan

I think the Steca is EN50438, but without the Irish variants. Are you sure they have the Irish version of EN50438? Q

quentingargan

quentingargan wrote: »

I think the Steca is EN50438, but without the Irish variants. Are you sure they have the Irish version of EN50438? Q

Oops - I stand corrected. Steca does have the correct standard. Thanks for that Freddyuk

air

That's positive at least.
Are all Steca branded inverters compatible?
Perhaps we could create a list of compatible inverters here since the ESB don't seem to maintain one on their website.

Bluefang

Once the GTI has a spec plate that states EN50438 it should be fine, I think it is the ESB that devised the spec in the first place to comply with Irish grid characteristics and of course, the conditions under which anti-islanding kicks in when an imminent mains failure is detected. Just be sure that the invertor vendor has a bullet proof returns policy in case you do encounter problems.

freddyuk

I have Steca certificates for the range up to 3000 watt including the 2010 watt which has slave units so covers most likely installations.

Not sure what a bullet proof returns policy means. If you install an inverter that does not comply then I would not give you a refund on the basis you got found out. Furthermore if the ESB did manage to discover you had an incorrectly certified inverter they would instruct you to disconnect your PV and I doubt they would consider allowing you to reconnect.

air

So are all Steca inverters compatible through appropriate software settings?