Hi

 

I am at the moment; considering installing some solar to offset our ever increasing electric bills.

I can't fit that many panels maybe 2.7kw or so but every little helps.

I see Sofar make a 3.3kw plug and play grid tie inverter.

Would this along with the associated safety switching be suitable for such a project?

 

I might add I'm a complete novice when it comes to solar but a competent DIYer. 

 

Thanks for any advice.

 

PR3.

 

Have a look at the system @007 RED has installed, it's almost exactly what you want to do.

 

Do you intend doing unofficial net-metering (spinning the conventional disc meter backwards) or joining (trying to join talk to @Thaifish) the official feed-in-tariff? (official system is not available to DIYers)

 

Sofar inverters (we have two, a 6kW grid tie and a 5kW hybrid) are not cheap but they are definitely robust and well engineered, they are also IP65 sealed and fanless.

 

If you're going to DIY have a look at my solar car-port thread. 

 

 

If using higher rated panel, then about 10 panels + 5kW inverter would be plenty for most households for daytime use, then using grid overnight.

 

We went with 8kW hybid inverter w/10kW ESS battery for overnight.  Which is perfect for us, IF, wanting to be OFF grid.  Still connected to the grid, and after a week of testing being Off Grid, we're now using grid overnight.  A cloudy, rainy week as it's been since installed, and our system is perfect for the house, Off Grid.   On sunny day, it's overkill, and using the grid at night, it's really overkill ... ????

 

We could have easily went with 5kW inverter, no ESS , using grid for overnight.  Would have halved our installation cost, which was not DIY.

 

We use 5kW over night, which would take our normal PEA monthly bill down to <฿600.  That would be down from the past year of ฿2500-3200 a month. 

 

You would need about 25m² of roof, using the panels we did, 540w.  1 panel being just over 2m²

@PR3the people on the solar thread are brilliant and free. ????

If you don't know then you can save all these conversations by hitting the 3 dots button, then share, then send it to your email address. That's what I'm doing until ready for a solar project. ????

Thanks for the guidance Gents.

I have been following the various forum threads going on at the moment in an attempt to garner a little knowledge and to decide what to do.

I'll try create a little clearer picture of what I'm up against.

We do have a large roof but the house is 2 floor and I'd much rather have the panels in a place I can keep an eye on them. 

Biggest problem regarding positioning is the unfortunate fact that I have no easy accessible (low down) roof space on the East or South side.

Which leaves me with my intended (at this point) installation site which is above the driveway.

The area will fit approx 2.7kw of panels possibly more.

6 x 455w comfortably maybe 7 at a push.

Our current usage is circa 1000 kwh per month or which the majority is used at night time.

The idea currently is to contribute to the load rather than mitigate it altogether; also not starting with the intention of net metering but if it happens ill have to install a means of stopping export on meter reading days.

There's a local electrical store here (Khon Kaen) that are having an offer on solar panels at the moment.

They're selling 455w mono half cuts for 4600 baht. Or 390w version for 3800 baht.

I've never heard of BQ Solartech though, does anyone have any experience with or knowledge of them?

Thanks 

PR3

 

 

 

Forgot to mention driveway is on the West side

48 minutes ago, PR3 said:

Our current usage is circa 1000 kwh per month or which the majority is used at night time.

Kind of defeats the purpose of solar.

Yes I have to agree and I fully understand why it would seem a little pointless given the info i provided.

I don't really have the spare money or room to install an all singing all dancing system.

 

So it'll have to be baby steps for now. 

Hi Gents,

 

I see this 5kv Sofar inverter has two separate PV inputs,

I've looked extensively online and cannot ascertain whether they're seperate circuits

i.e.the two inputs can be of different wattage/voltage and one won't affect the other if shaded for instance.

Many Thanks.

PR3.

1 hour ago, PR3 said:

Hi Gents,

 

I see this 5kv Sofar inverter has two separate PV inputs,

I've looked extensively online and cannot ascertain whether they're seperate circuits

i.e.the two inputs can be of different wattage/voltage and one won't affect the other if shaded for instance.

Many Thanks.

PR3.

Those are 2 strings , each with it's MPPT controller . They can be other side of house , or other angle . Inside the power will be combined , to create 1 flow of electricity .

The strings on this type of inverter is series creating high voltage . In this case , per string each 600V maximum . The voltage of the panels is always mentioned under VOC ( the highest number on the spec ) . So if you got 10 panels in series , and lets say they are 46 V , then you got a 460V string . However many panels on the market are still like 350watt panels , so in that case you would never be able to reach the 5000W output . So in order to get it , a 2nd string can be attached with also a number of panels , creating higher output .

Thanks so much for the clarification.

That's looking like the direction to go for me then, 2 strings..1 each side of the house. 

Thanks again.

PR3 

Hi Gents,

 

Ordered the inverter and a 12 panel fitting kit, will go get panels tomorrow.

I've been looking at the electrical side and seen this product on Laz.

I have read in other threads that AC and DC in same unit is unwise though?

Anyways here it is. 

Advice is always well received.

Cheers all.

On 8/13/2022 at 2:35 PM, PR3 said:

6 x 455w comfortably maybe 7 at a push.

Our current usage is circa 1000 kwh per month or which the majority is used at night time.

The idea currently is to contribute to the load rather than mitigate it altogether; also not starting with the intention of net metering but if it happens ill have to install a means of stopping export on meter reading days.

There's a local electrical store here (Khon Kaen) that are having an offer on solar panels at the moment.

They're selling 455w mono half cuts for 4600 baht. Or 390w version for 3800 baht.

I've never heard of BQ Solartech though, does anyone have any experience with or knowledge of them?

Check your choice or inverter can take panels this size.

Your data sheet suggests a max PV current of 11A per string.

My 330w panels can produce 10A ..... if your 455W panels produce 15A, you'll have a problem.

That's a very good point, the inverter is for 2x11amp strings. 

I'll have to check the panels max output, I went to the same shop the other day to do precisely that and forgot my reading glasses..Lol...the joys of ageing.

I'll check tomorrow and report back...oh <deleted> I'll be crossing my fingers on this one...eek

26 minutes ago, PR3 said:

That's a very good point, the inverter is for 2x11amp strings. 

I'll have to check the panels max output, I went to the same shop the other day to do precisely that and forgot my reading glasses..Lol...the joys of ageing.

I'll check tomorrow and report back...oh <deleted> I'll be crossing my fingers on this one...eek

Most panels will create higher voltage , but not that much rise in amps , in fact , i did not see a lot of +11 amp panels as of yet . I think your panels will be like 46/47v and around 9.8 amp , maybe up to 10.2 .

I'll bear all this in mind when I go spending in the morning i looked online it says 10.55 amp short circuit and 9.8 nominal so should be okay . 

They'll likely spend a week or more in store-room before I do anything with them are there any special considerations for storage I have an 8yo son and he's adventurous. 

Cheers.

 

6 hours ago, PR3 said:

I'll bear all this in mind when I go spending in the morning i looked online it says 10.55 amp short circuit and 9.8 nominal so should be okay . 

They'll likely spend a week or more in store-room before I do anything with them are there any special considerations for storage I have an 8yo son and he's adventurous. 

Cheers.

 

Well  , panels are pretty sturdy , as they are able to withstand years and years of weather , including hail and storms . I'd say , leave them in the carton , and put them straight up against a wall .

Things to look out for are , somebody walking on the panels (like a adventurous kid) and any light on the panels will create electricity . That electricity can potentially start a fire , inside the carton it is certainly no problem .  In case you unpacked them already , face them front side vs the wall and make sure the wires ( connectors) can't touch anything .

Thanks for the guidance I have a lockable room which will be suitable.

They'll be left in the packaging for now.

Cheers

14 hours ago, sezze said:

Well  , panels are pretty sturdy , as they are able to withstand years and years of weather , including hail and storms . I'd say , leave them in the carton , and put them straight up against a wall .

Things to look out for are , somebody walking on the panels (like a adventurous kid) and any light on the panels will create electricity . That electricity can potentially start a fire , inside the carton it is certainly no problem .  In case you unpacked them already , face them front side vs the wall and make sure the wires ( connectors) can't touch anything .

That raises an interesting subject for discussion... given panel prices have risen some 20% over the past 12 months, would it be worth investing in buying panels now for an installation that may be 6-12 months or more down the track?

 

Are prices likely to continue to rise or fall?

 

Maybe I should ask this in another topic rather than hijacking this one?

Since I've only recently paid more attention to prices of panels I'm not really certain which way they're likely to go or what they cost before.

The way the world appears to be heading into an inflationary phase so I didn't want to wait any longer. 

In the end I paid 42000 for 10 x 420w mono half cuts.

Inverter, fitting kits, junction box for another 29000.

Hopefully another 9000 will buy the rest, so 80000 plus my labour didn't seem so excessive for a 4.2 system or 3.4ish in reality.

Everything may very well get cheaper in the future but like many things in life it's a gamble I suppose.

I'm sure more experienced members will know more.

Cheers.

PR3.

 

That certainly is a difficult question . IMHO , for the next 6-12 months , i would certainly guess rising prices . This thx to inflation and energy costs rising in several parts of the world ( Europe) . Together with also electric cars ( sales numbers there very high , creating shortage on batteries ) i would expect for the coming y higher prices . On the possible lower price i can see only 1 thing . That is a big crisis , meaning the inflation together with energy crisis , will make the economy totally grinding to a halt .There are signs that it is happening right now , but lot's of money is still flowing to renewables .

On the other things needed for a installation . Inverters will go down in price and newer models will come out . Chip shortages are still a case , but i expect this to slowly recovering .Batteries are a different story . They will almost certain go up in price . Battery shortage is already the case for cars , and lithium prices are rising for a while .

If you check the situation and will invest now in panels then it is needed to ask yourself more questions .

A will you go with the battery option , it is the best , but also the most expensive . Solar panels are 2nd most expensive item . Having them already , you can already be saving electricity just by adding a supercheap inverter . Even when they are not ideally installed and everything , solar panels will make electricity if they see light .

Hi again,  good evening all, sorry for not replying I've been on furniture building duty ????.

You are of course right, the most advantageous manner in which to do this would be to go for the full monty so to speak with batteries, a suitable hybrid inverter for our power demands and a large array on the roof.

In honesty i have been reading other threads over the last few weeks and really started to lean that way and got totally carried away with my ideas and plans and tied myself in knots over it all.

In the end I had a to take a breath and remembered what the initial intention was. ....to keep things simple and use solar to contribute to our daytime usage of approx 15 units. 

And since it was intended to do this DIY where I felt comfortable to do so the roof was off the cards as I don't like heights.

Additionally there are budgetary constraints to consider.

Anyways; the items other than the panels should arrive soon.

Only thing left to consider are cables, trunking and any other safety devices necessary.

On that particular subject; would 4mm twin and earth (outdoor) be enough to connect to the MCB of the house? 

Also where would be the correct place in the MCB to connect the incoming supply?

Thanks

Cheers.

PR3

 

Smart idea ... just put some panels and a cheap inverter . Later on , you can extend the system if you wish to do so and you can do it with the money you saved from the electric bill .

Building a bigger and better system may very well be on the cards in the future. 

If the feed in rate was more attractive and not so bureaucratic I'd have probably gone in that direction to begin with.

I see the cost of electricity is rising by 68 satang per unit next month, better get those panels up soon.

Wonder if the feed in rate will rise along with it?

1 hour ago, PR3 said:

Building a bigger and better system may very well be on the cards in the future. 

If the feed in rate was more attractive and not so bureaucratic I'd have probably gone in that direction to begin with.

I see the cost of electricity is rising by 68 satang per unit next month, better get those panels up soon.

Wonder if the feed in rate will rise along with it?

Who cares .... the system is way to complicated to ever make use of it . Once the panels are up and running , you start saving money . You feel good about enviroment or not , all ok , at least you are creating a bit of electricity for yourself . Your bill goes down , you are happy .

3 hours ago, sezze said:

Your bill goes down , you are happy .

 

And, importantly in my case, so is Madam as she authorised shelling XXXXXX baht on my pet project. ???? 

4 hours ago, sezze said:

Who cares .... the system is way to complicated to ever make use of it . Once the panels are up and running , you start saving money . You feel good about enviroment or not , all ok , at least you are creating a bit of electricity for yourself . Your bill goes down , you are happy .

I totally agree.  I think putting up some panels and connecting them to a few fairly cheap GTIs, like the ones that @Crossy or @BritManToo originally used, would serve as a good learning exercise for  @PR3.

 

My small scale GTI system comprising 4 x 415W half-cut mono panels connected to 2kW Sofar inverter and is merrily churning out electricity, even with the poor weather (lots of clouds, rain and thunderstorms) that we have been having during the past month.  The system was originally designed with the aim of reducing my monthly bills by 75%, e.g. producing about 7 units per day.

 

Below is the production data graph from my monitoring facility for the current billing period July – August.

 

FYI…. The yellow bars on the 15 & 16 August indicate the days the system was switched to NO EXPORT as historically the meter reader can come on either of those days.  This month the system only managed to produce just over 164 units, as shown in the pie chart below, which is better that nought.

 

 

My system cost 28K THB and has been operational for 10 months now.  It’s on track for a ROI in approximately 2.5 years and given the pending price increase of electricity announce the other day payback may be even sooner ????.

 

I just spent 20 minutes writing a reply and it disappeared.

Thanks for the information 007 RED. What you have done and others in the past as you mentioned is pretty much exactly what is intended.

More bits arriving tomorrow hopefully. (Sofar 5KTLM and fitting kits for 12 panels)

AC/DC Combiner box arrived today with a little damage. (Broken bulkhead MC4 connectors on PV1) Shop sending 2 built up replacement. 

Crossy, since I'm a novice with such things would you cast an eye over the wiring to see if it's correct. I just find it confusing that the inverter output will enter the "out" of the voltage regulator in it current configuration. 

Anyways that's about it for now.

Back to man beatch duties and getting stressed about the fast approaching time of walking on the tin roof....oh the horror.

Cheers All

PR3.

Another arrival..its like Xmas.

Panel fitting kits just showed up too.????

Ordered some PV cables and 3 x 4mm for the inverter and connection to the property.

And the termination crimpers too along with MC4 wrenches and 10 extra connectors.

@007 RED when you connected the inverter supply cable to the MCB; would you kindly advise where you connected to?

If you have an image or two that would certainly help.

At this time just attempting to get my ducks in a row before starting the fitting part of this project.

I'll measure up and go buy trunking tomorrow. And maybe a decent earth rod for the lightning arrestors.

Cheers

PR3.