Solar Power

[blackcab]

I manage a building where the electricity bill is about 50k a month. The building's concrete roof has roughly between a third and half a rai of usable space.

Is it going to be financially feasible to generate electricity from solar power and sell it back to the MEA?

Or should I get a phone mast from True installed and get about 12.5k a month for nothing?

[Forkinhades]

Simple quick answer, get the phone mast.

It will take 10-15 years to get your investment back from Solar.

Not quite ready yet.

[surangw]

any chance to put in skylights?

we put them in our building and cut our day time elect use by 80%

[blackcab]

any chance to put in skylights?

we put them in our building and cut our day time elect use by 80%

I'd consider it, but I don't think the tenants would be too happy (it's an apartment block).

[Issangeorge]

Take another look at solar. If you can install a system for around ฿33000 a kWh, you should be able to pay it off at a kWh rate of around ฿3.55, amortized over ten years at 6% interest. Most panels are guaranteed for 25 years now, so you would have 15 years of free electricity.

[IMHO]

Take another look at solar. If you can install a system for around ฿33000 a kWh, you should be able to pay it off at a kWh rate of around ฿3.55, amortized over ten years at 6% interest. Most panels are guaranteed for 25 years now, so you would have 15 years of free electricity.

Are you aware of any vendors supplying & installing small (<=10kWh) solar grid tie systems at that kind of price? At that rate, factoring in the tarriff, ft and VAT I normally pay, payback would be as little as 4-5 years.

[Issangeorge]

No I am not , I have tried to find rates for Thailand on the internet, and cannot. However I do know that panels sell in China for as little as ฿17 a watt, but how much they would be imported and installed, I don't know, but for a large installation like an apartment building it would be worthwhile investigating, I think the prices are getting very close to a payback time of ten years at present electric rates, and then you would have about 15 years free electricity.

[IMHO]

Ok, you had me all excited for a moment there. The average price I see for non-megawatt projects in TH is around 60K baht/kWh

[Crossy]

Amorn Solar's biggest single-phase system (5.4kW) is 176,000 Baht but that's plus installation http://www.amornsolar.com/index.php?mo=18&display=view_single&pid=1559236

Getting in the right ball park

[blackcab]

To give you an idea if this would work for us, our electricity bills vary between 27,000 baht a month to 37,000 baht a month per property. Our tariff from the Bangkok MEA is the Small General Service 2.1.2:

2.1.2 : Below 12 kV

Service charge : 46.16 (baht per month)

First 150 kWh (1st 150th) 2.7628 (Baht/kWh)

Next 250 kWh (151st 400th) 3.7362 (Baht/kWh)

Over 400 kWh (up from 401st) 3.9361 (Baht/kWh)

These costs are plus the ft charge and plus VAT, which we have to consider a cost to the business. As the company trades in land and property and rents out apartment blocks the business cannot reclaim the input VAT as it's activities are VAT exempt.

[Issangeorge]

Amorn Solar's biggest single-phase system (5.4kW) is 176,000 Baht but that's plus installation http://www.amornsolar.com/index.php?mo=18&display=view_single&pid=1559236

Getting in the right ball park

So say ฿200,000 with installation amortized over 15 years at 6% is ฿1,688 per month. If you have 5 hours of sunlight a day and 200 days a year, it works out cheaper than I am presently paying, and then I would have 10 years of free electricity. Solar is here now if you can afford the upfront costs.

[blackcab]

How do these systems work in terms of using the electricity they generate? Is the electricity that is generated sold back to the MEA via a separate meter? Or is it wired into the apartment and used by tenants, thereby reducing our electricity bill?

[Crossy]

Small systems (and even some larger ones) simply spin the normal meter backwards when exporting power to the grid, the meter goes forwards again at night or when the power used is greater than that being created by the solar panels.

This is fine so long as you are a net importer of power, MEA / PEA get a little upset if you become a net exporter without a sell tariff.

Now it gets complex, there was a solar export mechanism called (IIRC) My Solar Roof which was a disaster mainly because membership was open for such a short time, approved equipment was very expensive and nobody actually advertised it.

The current government are attempting to revive the project, hopefully with sensible prices, contracts and sell rate.

There is a mechanism whereby large systems can sell to the grid now, but I have no idea what constitutes 'large' or how to go about getting connected.

[blackcab]

Thank you for the explanation. I am currently looking into whether it would save the business money to change electricity tariffs. The MEA has a separate tariff for hotels/apartments (tariff 5.1.3), but the billing system is quite complex.

To calculate your bill the MEA needs to know information that I believe can only be obtained by adding done some sort of measuring device to the building supply (possibly a new meter that records this information).

I am hoping that the business could be supplied data from these measurements so we can see what our minimum useage is. Based on this, I could then estimate how many solar devices we should potentially budget for.

[stubuzz]

Have you considered wind turbines? They work 24 hours a day.

[blackcab]

Have you considered wind turbines? They work 24 hours a day.

I haven't, but if they gave more for less then I would. In my experience there doesn't seem to be much wind on the roofs in question, but then again that's just a casual observation.

Is wind power more profitable than solar power?

[stubuzz]

I'm not sure if it's more profitable, but maybe a hybrid system to take the benefits of both would be an idea.

[Deke]

The size of the roof (0.3 - 0.5 rai) is very much in line with current government incentives for rooftop solar. In my opinion it would be fairly easy to make an economic argument for developing it. Otherwise, there are companies that will lease the rooftop and develop it themselves for much more than you would get from True.

[blackcab]

That's very interesting. I work for a reasonably traditional Thai company. If I can justify something that can make money or save money, I stand a good chance of getting it done. What I can't do is cover a number of rooftops with solar panels and wind turbines without some strong numbers to back it up.

Considering the low take up of renewable energy in a country with so much sun, this is something I will have to sell quite hard.

[Deke]

That's very interesting. I work for a reasonably traditional Thai company. If I can justify something that can make money or save money, I stand a good chance of getting it done. What I can't do is cover a number of rooftops with solar panels and wind turbines without some strong numbers to back it up.

Considering the low take up of renewable energy in a country with so much sun, this is something I will have to sell quite hard.

I've sent you a PM. We would be glad, with no obligation on your part, to take a look and run the basic numbers to give you an idea of what might be possible.

[IMHO]

The solar Rooftop program phase 2 is back guys - applications close at the end of this month.

For domestic systems < 10kWh, the buy rate is 6.85 Baht/unit.

[Crossy]

The solar Rooftop program phase 2 is back guys - applications close at the end of this month.

For domestic systems < 10kWh, the buy rate is 6.85 Baht/unit.

Got a link Mate?

I really fail to understand why they limit applications so.

[IMHO]

The solar Rooftop program phase 2 is back guys - applications close at the end of this month.

For domestic systems < 10kWh, the buy rate is 6.85 Baht/unit.

Got a link Mate?

I really fail to understand why they limit applications so.

Only links are in Thai I'm afraid:

PEA:

https://www.pea.co.th/vspp/Pages/Solar%20Rooftop.aspx

MEA:

http://www.mea.or.th/profile/index.php?l=th&tid=3&mid=3031&pid=3030

This vendor site is maybe more useful:

http://www.thaisolarfuture.com/product.php?id=9

[Crossy]

This page (from the vendor linked to by IMHO) http://www.thaisolarfuture.com/product.php?id=10 may be of interest to our OP.

[GinBoy2]

I've been contemplating the move to solar for a while. Now I'm one of the aircon junkies and in hot season my PEA bills can hit ฿10K/Month, so electric cost vs initial investment is a prime consideration.

But my thinking is this. If you have money sat in the bank earning maybe 2%, the ROI on monthly saving vs what you're earning in the bank it becomes a very viable option. Now if you're borrowing money to do it, well then the question is a little harder to answer definitively.

[Crossy]

We've just put up a double carport which just happens to be oriented correctly for solar. Probably going to put a couple of kW on there to see how it works out.

[Issangeorge]

Crossy, my one roof faces directly south, has no shade and I'm at 16.45˚ latitude, normal roof slope, do you have any idea how many hours direct sunlight I would get on a sunny day, or a site to go to that would help me?

[Deke]

Crossy, my one roof faces directly south, has no shade and I'm at 16.45˚ latitude, normal roof slope, do you have any idea how many hours direct sunlight I would get on a sunny day, or a site to go to that would help me?

I hope you don't mind if I step in. The capacity factor for most of Thailand is 15% - 16%, so you can figure 0.16 x 365 days x 24 hours = 1,402 hours/year.

If the slope of your roof is much more than 16.45 degrees, then you should adjust the output slightly downward to account for that as well.

[Issangeorge]

I've been contemplating the move to solar for a while. Now I'm one of the aircon junkies and in hot season my PEA bills can hit ฿10K/Month, so electric cost vs initial investment is a prime consideration.

But my thinking is this. If you have money sat in the bank earning maybe 2%, the ROI on monthly saving vs what you're earning in the bank it becomes a very viable option. Now if you're borrowing money to do it, well then the question is a little harder to answer definitively.

Looking at the installation Crossy posted I figure if you average 450kWh a month, and that is probably a lowball estimate, if you loan yourself the money at 2% interest and pay it back at ฿2.86 per kWh, in 15 years you will have paid your self back at a constant rate that won't go up over time and is about 33% below present electric costs, and of course after you are paid back, you will have ten to twenty years of free electricity. Solar is here now. I wish I had the money to invest in it and was young enough I could be guaranteed to enjoy the free years.

[Crossy]

Crossy, my one roof faces directly south, has no shade and I'm at 16.45˚ latitude, normal roof slope, do you have any idea how many hours direct sunlight I would get on a sunny day, or a site to go to that would help me?

One of many http://www.ecowho.com/tools/solar_power_calculator.php

There are also many calculators that adjust for non-optimal panel angles, Google is your friend.