Estimated Contractor Costs to install Grid Tie Solar System

[dinga]

I've been following the Solar thread for quite a while, and am in awe of the skills of the TV Members who have installed their own systems.  Sadly, that's well beyond me so I'm looking for advice about:

1.  Whether a contractor will do the installation if I provide all the necessary hardware

2.  If yes, what are the likely installation costs to do so?

3.  Where am I likely to find such a contractor?  (I live in Rayong).

 

By way of background:

*  The actual, annual electricity consumption in our current (pun not intended...) beach bungalow is:  2021/2022 - 3,455 units;  2022/2023 - 3,162 units

*  We are presently having a house built on a (very) small orchard, and when the house is finished we are likely to spend 50% of the time at each location.  I estimate that the annual electricity consumption at each location will be:  Orchard:  2,275 units;  Bungalow: 1,725 units.

*   While the potential savings are not hugely significant, I like the thought of reducing electricity costs with a small GTi Solar system at both locations [2 panels at the bungalow and 3 panels at the orchard were estimated at reducing the annual costs by some 70% - assuming feed-back to the grid.

*  That aspiration was torpedoed by a local quote for 43,000 baht for the supply and installation of only the 2 panel system (ea 420W).  On top, the contractor advised A. Installation services only are NOT provided; B. Feed back to the grid is illegal and would not be available (don't know if the invertor has the ability to do so).  In any event, at that price solar simply does not make economical sense for us. 

 

Hope someone can offer a possible way forward

 

      

 

 

[DJ54]

Interested in installing a small system here in Kumphawapi to offset the electric bill that jumped about 25% of normal when used on hot days.

[007 RED]

@dinga  Welcome to the Alternative/Renewable Energy Forum.

 

Approximately 3 years ago I was inspired by @Crossy original post “How about a solar carport on a budget”.

 

 

I appreciate that this post has expanded considerably since it was started ( now 23 pages), but I would suggest that you take the time to read through it as it will give you a wealth of information from various forum members who have ventured into solar, including myself.

 

In fact I've just noticed that on page 18 of @Crossy original post, you asked me a range of questions about my system, to which I subsequently responded.

 

FYI…. I only had a limited knowledge of electrical systems which was acquired when did my degree in control system technology, some 55 years previously.  That said, DIY was inbuilt into my DNA, so considering such a project at my age (then 73 YO) presented a wonderful challenge and great learning experience, especially during the pandemic lockdown.

 

Like you, our (my wife and I) electricity usage was relatively low, with an average usage of about 280 units/month over the preceding 2 years.

 

I decided that we would go for a simple grid tied system with the aim of reducing our monthly usage by 75%.  As a result, I opted for 4 x 415W half cut mono panels linked to a 2kW grid tied inverter.

 

The panels would be mounted onto our carport roof, which is South facing and angled at approximately 15^o, which was almost ideal for our location (24 km West of BKK). 

 

The inverter and breakers are mounted in the shade under the roof of the carport below the panels.

 

The total cost of the hardware was 28,000 THB, give/take a few THB.  It was a DIY installation, with basic tools, so no additional labour costs, just my time and effort.

 

The system has now been running for 18 months and has saved us approximately 18,000 THB off our electric bills.  I estimate that ROI will be approximately 2.5 years based on the cost of the electricity (4.2 THB/unit) when the system was commissioned.  Not a bad investment when compared to the inept interest rates paid by banks these days.

 

The major drawback with our gid tied system is that when the sun is shining brightly, with no clouds and we are only using minimal appliances within the house, our old type of electric meter spins backwards at a 'fair rate of knots' because the solar system is then feeding surplus power back to the grid.

 

This is something that you don’t want your local PEA to see as it is in fact illegal.  If they (PEA) discover you are back feeding, at best they will fit a digital meter which wont spin backwards.  At worse they can demand that you remove/disconnect the solar system and/or pay a fine (10 x the estimated loss of revenue) and/or threaten to disconnect you from the grid.

 

Many of us the have a simple grid tied system, with an old type of meter which can merrily spin backwards, are all to aware of the need to 'not to export' on the day that the meter reader comes or to go into a negative meter reading situation, that is to say the current meter reading is less that the previous one, as that will ring alarm bells with the PEA.

 

In your current post you mentioned that a contractor indicated that feedback to the grid would not be available.  This is because the contractor is well aware that they may well become liable if the PEA discovered your system was back feeding into the grid.

 

For a solar system to be approved by the PEA to back feed, there is a complex set of rules/regulations which must be adhered to, coupled with a massive amount of paperwork, which increases the cost of an installation and ‘commission fees’ considerably.

 

Please don’t be put off.  If I can do a DIY set up at my age with limite electrical experience/knowledge, so can anyone else with a reasonable degree of applied common sense. 

 

Don't hesitate to ask questions, that's what the forum is for.

 

Good luck.

[DJ54]

11 minutes ago, 007 RED said:

@dinga  Welcome to the Alternative/Renewable Energy Forum.

 

Approximately 3 years ago I was inspired by @Crossy original post “How about a solar carport on a budget”.

 

 

I appreciate that this post has expanded considerably since it was started ( now 23 pages), but I would suggest that you take the time to read through it as it will give you a wealth of information from various forum members who have ventured into solar, including myself.

 

In fact I've just noticed that on page 18 of @Crossy original post, you asked me a range of questions about my system, to which I subsequently responded.

 

FYI…. I only had a limited knowledge of electrical systems which was acquired when did my degree in control system technology, some 55 years previously.  That said, DIY was inbuilt into my DNA, so considering such a project at my age (then 73 YO) presented a wonderful challenge and great learning experience, especially during the pandemic lockdown.

 

Like you, our (my wife and I) electricity usage was relatively low, with an average usage of about 280 units/month over the preceding 2 years.

 

I decided that we would go for a simple grid tied system with the aim of reducing our monthly usage by 75%.  As a result, I opted for 4 x 415W half cut mono panels linked to a 2kW grid tied inverter.

 

The panels would be mounted onto our carport roof, which is South facing and angled at approximately 15^o, which was almost ideal for our location (24 km West of BKK). 

 

The inverter and breakers are mounted in the shade under the roof of the carport below the panels.

 

The total cost of the hardware was 28,000 THB, give/take a few THB.  It was a DIY installation, with basic tools, so no additional labour costs, just my time and effort.

 

The system has now been running for 18 months and has saved us approximately 18,000 THB off our electric bills.  I estimate that ROI will be approximately 2.5 years based on the cost of the electricity (4.2 THB/unit) when the system was commissioned.  Not a bad investment when compared to the inept interest rates paid by banks these days.

 

The major drawback with our gid tied system is that when the sun is shining brightly, with no clouds and we are only using minimal appliances within the house, our old type of electric meter spins backwards at a 'fair rate of knots' because the solar system is then feeding surplus power back to the grid.

 

This is something that you don’t want your local PEA to see as it is in fact illegal.  If they (PEA) discover you are back feeding, at best they will fit a digital meter which wont spin backwards.  At worse they can demand that you remove/disconnect the solar system and/or pay a fine (10 x the estimated loss of revenue) and/or threaten to disconnect you from the grid.

 

Many of us the have a simple grid tied system, with an old type of meter which can merrily spin backwards, are all to aware of the need to 'not to export' on the day that the meter reader comes or to go into a negative meter reading situation, that is to say the current meter reading is less that the previous one, as that will ring alarm bells with the PEA.

 

In your current post you mentioned that a contractor indicated that feedback to the grid would not be available.  This is because the contractor is well aware that they may well become liable if the PEA discovered your system was back feeding into the grid.

 

For a solar system to be approved by the PEA to back feed, there is a complex set of rules/regulations which must be adhered to, coupled with a massive amount of paperwork, which increases the cost of an installation and ‘commission fees’ considerably.

 

Please don’t be put off.  If I can do a DIY set up at my age with limite electrical experience/knowledge, so can anyone else with a reasonable degree of applied common sense. 

 

Don't hesitate to ask questions, that's what the forum is for.

 

Good luck.

Red thanks for the detailed information. Not knowing much about solar and where to buy hardware to do DIY … I’d go with a set-up/size similar to yours… any suggestions? Have prices for hardware increased or about the same?
 

The current lecky bills is 25% more than the usual over last 2 years. 
Think it’s time to offset some with solor…

 

Thanks 

[007 RED]

39 minutes ago, DJ54 said:

Red thanks for the detailed information. Not knowing much about solar and where to buy hardware to do DIY … I’d go with a set-up/size similar to yours… any suggestions? Have prices for hardware increased or about the same?
 

The current lecky bills is 25% more than the usual over last 2 years. 
Think it’s time to offset some with solor…

 

Thanks 

NO problem... glad to help.

 

I'm not sure on today's prices of hardware, so give me a few days and I'll do a bit of research and come back to you with some info.

[007 RED]

On 4/20/2023 at 4:19 PM, DJ54 said:

Red thanks for the detailed information. Not knowing much about solar and where to buy hardware to do DIY … I’d go with a set-up/size similar to yours… any suggestions? Have prices for hardware increased or about the same?
 

The current lecky bills is 25% more than the usual over last 2 years. 
Think it’s time to offset some with solor…

 

Thanks 

As requested, I done a little research and as expected the costs of the hardware used in my small scale solar installation 18 months ago has risen.

 

Inverter  Sofar   2200TL-G3 Single Phase Grid Tied Inverter

A search via Google at the time showed multiple suppliers within Thailand.  I opted for a company called Chang-Store.com. based in Chai Nat.  Their price was 9,500 THB which was one of the lowest at the time and included delivery by DHL.  Because this model of inverter does not come with a current transformer (CT) in the box, they provided one FOC.

 

Although the company still has its own website, they now also have a presence now on Shopee.  Their current list price on both their own website and Shopee is now 12,900 THB, but I don’t know if this includes delivery or if they will still include the CT free of charge..

 

So, inverter is now 3,400 THB more expensive.

 

Solar Panels    Sunpal   SP415-72H Monocrystalline Half-Cell

A search on Google at the time indicated several suppliers of this make/model of solar panel on Shopee and Lazada, with a price ranging from 4,000 to 4,500 THB, which did not include delivery. 

 

During a trip into BKK one day I noticed a shop (Roove Solar) that had recently opened and were displaying solar equipment, so my better half and I paid them a visit a few days later.  As it happened, they stocked the make/model that I was interested in and their price being 4,000 THB per unit.  My better half managed to get them to discount the price to 3,800 THB each, plus free delivery, if we cash purchased the 4 panels I required.

 

The shop is still open.  However, they have Facebook and Shoppe presence which only shows a limited product range so I’m not able to give their current price of the make/model of solar panels.  A google search for the make/model of solar panels now shows a price range around 5,200 THB plus delivery costs.

 

So, the solar panels are now appear to be about 1,800 THB each more expensive.

 

Mounting Brackets

20 off, 1.2mm thick stainless steel were made by local 'tinsmith' from off cuts @ 50 THB each.

 

I’m not sure if I could get them for the same price today as at the he gave us a very good discount due to the fact that we had recently ordered a large number of bespoke stainless steel cupboards and double sink unit for our washroom.  I have estimated that the cost today would be approximately 2,000 THB.

 

Ancillaries

Isolator boxes (appropriate circuit breaker + surge arrestor), cable, MC4 plugs all ordered online via Shoppe.  Cost approximately 2,300 THB.  Looking up the items today indicates a total price increase of approximately 400 THB.

 

Cost at Time of Installation			Cost Today
Inverter	X1	9,500	12,900
Solar Panels	X4	15,200	20,800
Mounting Bracket	X20	1,000	2,000
Ancillaries	Various	2,300	2,700
TOTAL COST		28,000	38,400

 

As shown above, the cost of hardware for my installation have increased by 10,400 THB.  The biggest increase being the cost of the solar panels, which could well be due to the world shortage of silicon chips.

 

Obviously using Google you may well be able to find cheaper alternatives.

 

I hope this helps and good luck.

[streetlite]

What kind of savings do you recoup from this setup?

[007 RED]

33 minutes ago, streetlite said:

What kind of savings do you recoup from this setup?

As at 12:00 Hrs today, my small scale system has produced 4,460kWh of power since it was first turned on 18 months ago.

 

Based upon the unit cost of electricity on the day the system was turned on (4.2 THB per unit), the system has saved us 18,730 THB on our electric bills.

 

As I've mentioned in my post above, the system cost 28,000 THB, so I estimate the ROI will be approximately 2.5 years.  That said, given the increase in the cost of electricity the ROI is likely to be nearer 2 years.

 

How many savings accounts/investments will pay you 18,730 THB interest on 28,000 THB, in 18 months?

[motdaeng]

@ 007 RED, i appreciate you sharing all the useful information.

 

i hope it's alright to mention the following points: 
- the ROI will much longer if you do not feed (your excess from the solar) back to the grid.
- it will be difficult to financially justify a solar installation if your electric use is low, especially if you cannot do the installation by yourself and you won't feed back to the grid ... (like in my case, about 200 units per months ... but i still think about it ... ).
- if you are not at home during the daytime and therefore your use of electricity primarily is overnight, you need to install ESS (energy storage system), which is expensiv.

 

 

[DJ54]

6 hours ago, 007 RED said:

Obviously using Google you may well be able to find cheaper alternatives.

 

I hope this helps and good luck.

Thanks for that Red… appreciated

[Pink7]

6 hours ago, 007 RED said:

As at 12:00 Hrs today, my small scale system has produced 4,460kWh of power since it was first turned on 18 months ago.

 

Based upon the unit cost of electricity on the day the system was turned on (4.2 THB per unit), the system has saved us 18,730 THB on our electric bills.

 

As I've mentioned in my post above, the system cost 28,000 THB, so I estimate the ROI will be approximately 2.5 years.  That said, given the increase in the cost of electricity the ROI is likely to be nearer 2 years.

 

How many savings accounts/investments will pay you 18,730 THB interest on 28,000 THB, in 18 months?

Very impressive.

 

Pink