Just installed Hybrid Solar PV at my house

[Noble_Design]

Over the weekend I just had a hybrid solar PV system installed at my house due to the crazy increase of electricity tariffs lately.

This is a hybrid system which means the PV also charges a battery which in case of a power outage from the grid will still be able to power up the house hold.

Power outages has been quite frequent at my housing area due to the frequent thunderstorms. 

Anyway I'll explain further with the accompanying pictures:

So here you have the PV panels themselves. Monocrystalline 460W each. Originally I planned to have 11 of them installed to give me a total max output of 5,060W but unfortunately the side of my roof can only accommodate 6 panels while the rear roof can only install 4. It will be a bit weird and a bit more expensive to run the wires to the other side of the roof just to accommodate another 1 panel so decided 10 panels for a max output of 4,600W should be ok.

The hybrid inverter and the associated breakers for the system, the electricity from the PEA's grid and for the battery. The inverter will decide based on the load of the house whether to use electricity from PV only, PV+battery, or PV+battery+grid electricity. At night time it will automatically switch to using battery power or combination battery + grid if needed.

At 10.20 AM yesterday on a cloudy morning I was still getting a respectable 2.9kW from the PV. I can't wait for this week's stormy weather to pass so I can check again the max output at 12 - 1 PM when the sun shines the brightest.

And this is the LifePO4 battery with a capacity of 11kW/h which serves as both backup power during power outages and provides power during night time. This battery is enough for my household's 2 A/C unit running the whole night.

[Guest1]

So you are not sending power back in to the grid?

Which would make your meter count backwards, just sayin' 

Aside, I think you could have installed minimum 3 more pannels, 2 over the 6, 1 over the 4, horizontal, or 6 more (4+2) vertical like the others.

Actually you still can, later. ;-) 

Nearly like this?

Interested to read about the numbers over a month later. How much savings do you have.

(Still think that getting the units for free in the night, aircon on, because you uploaded some power in daytime, might be the better deal?)

[Noble_Design]

34 minutes ago, Guest1 said:

So you are not sending power back in to the grid?

Which would make your meter count backwards, just sayin' 

Aside, I think you could have installed minimum 3 more pannels, 2 over the 6, 1 over the 4, horizontal, or 6 more (4+2) vertical like the others.

Actually you still can, later. ;-) 

Nearly like this?

Interested to read about the numbers over a month later. How much savings do you have.

(Still think that getting the units for free in the night, aircon on, because you uploaded some power in daytime, might be the better deal?)

Not yet, will look into selling back the excess electricity to PEA in the future. That would involve making an application and subject to their approval before we can sell back the excess power.

The battery does offer a further security during power outages which unfortunately is happening quite frequently at my area around 1-2 times a week for an hour each time so having the pleasure of not worrying about the next power outage every time there's a storm is quite a nice feeling.

[Guest1]

1 hour ago, Noble_Design said:

Not yet, will look into selling back the excess electricity to PEA in the future.

I am not talking about selling back. That needs changes in meter and some other adjustment to the grid.

I am talking about "giving it back", just for the meter count. Because you will never get the price per unit, you would have to pay, getting it back from them. So it is the best deal. Just secure your home grid, afaik the rest will just work fine. With this little amount of power send back into the grid. Or get more battery capacity, to keep all. Just need to be enough to run at least all without the air, methinks. Maybe even the Air,  perhaps without the compressor?

In Europe, some people are using single/double balcony solar panels for that. Just plugging it in to the socket. If there fridge runs, or whatever, that is using up the solar first. If they dont have any use for power, it count backwards on the meter. As long you arent having a smart meter, that is easy going. Of course, the power Co's dont like that. But as long it works, ....!

You just need to stop "charging" into the grid, while they changing the meter over the "last month" little numbers. ;-)

 

[KaptainRob]

16 hours ago, Noble_Design said:

At 10.20 AM yesterday on a cloudy morning I was still getting a respectable 2.9kW from the PV. I can't wait for this week's stormy weather to pass so I can check again the max output at 12 - 1 PM when the sun shines the brightest.

Looks like a good installation.  Who was the supplier and what was the approx total cost - PM if you prefer.

5 years ago it was nigh on impossible to get anyone in CM to quote on such an installation unless one paid a deposit ... then they'd come and look.

[Noble_Design]

A bit of update since the weather has been improving these few days. I managed to get 3.6kW out of the PV at 1:13PM, there are some clouds however they don't seem to be obstructing the sun. So on this day I am getting a sun to electric efficiency rate of 3.6/4.6 = 78.2%

 

As for usage, I turned on 1 A/C (9000 BTU) and 1 fan at the living room, the fridge and TV is running and I think I was also using the microwave at that time. My consumption was 1.56kW

This means I have an excess of about 2kW which goes into the Li battery as you can see from the diagram above. I just realized that the battery has an advantage of acting as a buffer to supply power when the sun is suddenly obstructed by passing clouds and the PV output drops below my consumption requirement.

Will be looking into selling back the excess electricity to the PEA soon.

[Marc26]

If you could provide an estimate of the cost, I the a lot of us would be interested 

 

Thanks 

[Noble_Design]

9 hours ago, Marc26 said:

If you could provide an estimate of the cost, I the a lot of us would be interested 

Thanks 

The cost is around 180,000 baht for my system. It would be cheaper if the system does not include a battery like mine.

[Noble_Design]

I'm thinking for my next upgrade to install some wind turbine so that when the sun is down I can still get some electricity from wind power. My inverter can be hooked up to a wind turbine as well as long as the power produced is at 48V.

However the guy who installed my PV said that it's not really recommended since the place where I stay isn't really windy. He said wind power is more suited for areas near the beach so I will be looking forward to installing them at my retirement land at Chanthaburi.

Anyway some of these wind turbines on sale at Lazada/Shopee is really dubious. With just a blade diameter of 1.2m they claim a power output of 4.2kW? That's almost as much as my PV from turbine slightly bigger than beer bottle LOL.

[KaptainRob]

4 minutes ago, Noble_Design said:

Anyway some of these wind turbines on sale at Lazada/Shopee is really dubious. With just a blade diameter of 1.2m they claim a power output of 4.2kW? That's almost as much as my PV from turbine slightly bigger than beer bottle LOL.

At what RPM?  Designed for and extremely popular on cruising vessels, the 'budget' models require a near hurricane force to reach max output and the noise is comparable to a multi-engine Antonov at take-off speed.  Slight exaggeration, but you get the point.

What was your monthly kwh consumption prior to PV install and what % reduction are you anticipating? 

[Noble_Design]

1 hour ago, KaptainRob said:

At what RPM?  Designed for and extremely popular on cruising vessels, the 'budget' models require a near hurricane force to reach max output and the noise is comparable to a multi-engine Antonov at take-off speed.  Slight exaggeration, but you get the point.

What was your monthly kwh consumption prior to PV install and what % reduction are you anticipating? 

This is the spec that the seller posted in Lazada for the 3,600 baht turbine:

Specification:
Rated power:4000W
Maximum power:4200W
Rated voltage:12V/24V
Start up wind speed:2.0m/s
Rated wind speed:11.5m/s
Survival wind speed:55m/s
Top net weight:6.2kg
Wheel diameter:1.3m
Blades number:5

Perhaps the 4.2kW is only obtainable at 55m/s which is the max wind speed it can handle. I'm pretty sure I won't be needing so much electric when the wind is blowing at almost 200km/h outside. I'll be looking for shelter instead.

Before the PV installation my monthly consumption is about 650-700 kWh which translates to a bill of about 3,000 baht. Incidentally I just received my latest bill yesterday about 2 weeks after installation of the PV. The bill turns out to be 450 kWh or almost 2,000 baht.

Bear in mind that in the 2 weeks that I have installed the PV, I was not able to use the battery at night for 1 week due to setup issue. Apparently the inverter was setup to use the battery only in the event of power down from the grid so essentially the battery was setup more as a UPS as oppose to supplying power when the PV is not operating. The installer came to my house a week later and in just 5 minutes the battery is setup to supply power when the PV is not operating (e.g. night time).

Also in these past 2 weeks the weather has not been so good what's with the rain and storm so there were a few days when my battery was not charged fully for night use. All said I am still very pleased of the savings in just half a month. 

Now with the battery properly set up and if the weather remains the same (rainy+storms) I am expecting a minimum saving of about 400kWh/month (worst case scenario) and if the weather gets better I'm expecting a saving of 500kWh/month.

So that's a saving of 2,000 baht/month (minimum) to 2,500 baht/mth (maximum).

That means the system will pay off itself in 6 years (soonest) to 7.5 years (latest)

 

[KaptainRob]

11.5 m/s = 40 kmph which is probably way more than you'd get except during a squall unless you're close the coast.

Your previous monthly average is similar to ours but we have a pool and irrigation.  Perhaps your a/c use is way more?  We seldom use more than 4hrs a/c daily.

Good results so far and the way PEA prices are going you'll be well compensated before those PV's wear out.

[Marc26]

8 hours ago, Noble_Design said:

The cost is around 180,000 baht for my system. It would be cheaper if the system does not include a battery like mine.

Thank you

It is sunny and baking at my wife's new house..............

 

So may be something to look at

[Noble_Design]

14 hours ago, KaptainRob said:

11.5 m/s = 40 kmph which is probably way more than you'd get except during a squall unless you're close the coast.

Your previous monthly average is similar to ours but we have a pool and irrigation.  Perhaps your a/c use is way more?  We seldom use more than 4hrs a/c daily.

Good results so far and the way PEA prices are going you'll be well compensated before those PV's wear out.

Yes we have a 9,000 BTU A/C in the living room which we will usually turn on by 1 or 2 PM and stays on till 6 PM. At night time there are 2 A/Cs - 15,000 BTU & 9,000 BTU turned on for 7-8 hours.

Yeah those PV has a warranty of 20 years from the manufacturer so hopefully in the long run it'll be a good saving.

14 hours ago, Marc26 said:

Thank you

It is sunny and baking at my wife's new house..............

So may be something to look at

Sooner or later every house will be equipped with it

[Noble_Design]

On the 25th of Jul I did some tracking on how fast the PV could charge my battery since the weather was quite good on that day. Bear in mind the PV wasn't just sending all the power to the battery, I was also running the washing machine, 2 big fans, microwave and steamer for my breakfast and lunch. Also the fridge was running constantly (although in fairness it only uses about 60-70W) and the TV (55" LED) was turned on too.

My battery capacity is 11kW/h. This is the result:

The biggest jump was between the hours of 11:20AM until 12:23PM. Within an hour I managed to charge 25% or 2.75kW/h. I was getting about 3.4-3.5kW from the PV at that time, the very clear sky and bright sun certainly helped a lot. Also I was already done with the washer, microwave and steamer before that so the house wasn't consuming a lot of power.

Once I got the battery to 100% I switched on the A/C at the living room from 1:00 PM until 5:00 PM cooling the house using power just from the PV. The stored power in the battery is for my A/C usage at night time.

Here's a shot of the PV's from the side of my house. Couldn't get a better shot since my house is 2 storeys.

[KaptainRob]

Impressive results 

[Noble_Design]

I'm glad I installed this PV

https://www.bangkokpost.com/thailand/general/2355601/all-time-high-power-tariff-expected

Without it, my monthly bill would have increased by almost 20%!

That means my payback period for this investment has effectively been reduced by almost 1.5 years

[Thaidup]

On 7/18/2022 at 12:15 PM, Noble_Design said:

The cost is around 180,000 baht for my system. It would be cheaper if the system does not include a battery like mine.

Just doing some figures, for me.

180,000 divided by 1000 a month = 180 months = 15 years,

For me is fine, Im only 58 years old and I intend to spend the rest of my life in the house  I currently reside in with the Thai wife.

So by the time Im 73 years old I can count on free power, unless in 15 years the units fail and I have to replace them 1 at a time?

[KaptainRob]

PV cells easily last 20 years and more likely between 25 and 35 years unless damaged by severe weather and falling trees.  The batteries will require replacement a number of times and cost depends on type chosen.

 

[Noble_Design]

16 hours ago, Thaidup said:

Just doing some figures, for me.

180,000 divided by 1000 a month = 180 months = 15 years,

For me is fine, Im only 58 years old and I intend to spend the rest of my life in the house  I currently reside in with the Thai wife.

So by the time Im 73 years old I can count on free power, unless in 15 years the units fail and I have to replace them 1 at a time?

Seems that you would like to cut your electricity bills by about 1,000 baht a month? In that case you don't need a 5kW system like mine.

Mine is tailored for reduction of 2,000 - 3,000 bath. So for you a 2.5kW or 3kW system should be enough. That means instead of 11 panels, you only need 6 panels. 1 panel cost about 8,000 - 9,000 baht so you only need to spend 135,000 baht.

And maybe you don't need a battery for your system if most of your usage is during day time when the solar power is sufficient. That is an additional 40,000 baht reduction. So in the end it's just 90,000 baht which means your pay off period is just 7.5 years.

The beauty of solar power is that it's scalable. So maybe now you need only 3kW and if in the future you need additional power you just add the panels or battery if you require.

[Noble_Design]

10 hours ago, KaptainRob said:

PV cells easily last 20 years and more likely between 25 and 35 years unless damaged by severe weather and falling trees.  The batteries will require replacement a number of times and cost depends on type chosen.

Yes the warranty for the PV themselves are 20 years and they should last longer than that.

As for the batteries, they may cost 40 - 50k baht now, but I expect by the time I need a replacement which I think should be around 10 years time the cost would have fallen to around 10k baht.

In 20 years time? Probably a few thousand baht.

[Noble_Design]

Cost of PV

I would like to share a bit what goes into the costs of my PV so if any of you would like to install them you can compare with my prices:

1) PV panels - Cost range from 6,000 to 9,000 baht per piece. A typical 5kW system will need around 11 pcs so total around 85,000 baht. They can be cheaper if they are polycrystalline but poly is less efficient converting solar energy to electricity than monocrystalline . Also if you research the prices on the internet, the cheaper prices are usually for bulk purchases (think >100 panels) which is more than what an end user would require. You can get cheaper prices too if you buy direct from the manufacturer (usually from China) but you might encounter issues during warranty claims if they ever arise.

Being one of the most important part of the system, it will be wise for you to spend a bit more for monocrystalline panels that are more efficient and from a reputable local supplier who would be able to support you if ever there's warranty claim. Remember these panels have a 20 years warranty, ask for the PV panels receipt from your installer if possible. Your installer may one day stop doing business but the panel local distributor should still be able to assist in the long run.

 

2) Inverter - Aside from the panel this is the second most important part of your system. The cost of the inverter depends on the rated conversion power, whether it is single or 3 phase, and whether it is off-grid, on-grid or hybrid. The higher the wattage the more expensive they are. Same goes if it's 3 phase or hybrid, they are usually more expensive than single phase or off-grid/on-grid.

A typical 5000W generic single phase hybrid inverter would cost around 25,000 - 30,000 baht. A branded one such as Huawei would set you back around 40,000 baht

 

3) Breakers, switches, wires/cables, railings for the PV panels, boxes for inverter and breakers installation  - around 5,000 - 10,000 baht

 

4) Battery - if you intend to go off grid or hybrid then a battery is a must. An 11kW capacity Li battery like mine would cost around 50,000 to 60,000 baht

 

5) Workmanship cost - around 10,000 - 15,000 baht for 2 days work. A reputable supplier would also provide free cleaning services for the panels for the first few years and would check on the system periodically either on-site visit or on-line (the inverter can connect to the wifi) 1 or 2 weeks after installation to verify that everything is running as it should.

[Noble_Design]

 

Scalability of PV and function of inverter

 I have replied to a question about scalability of PV and would like to expand on this topic further. A PV system can be tailored to your budget and requirement. The number of PV panels installed correlates directly to the amount of power generated. More panels = more power.

 

However you will also need a corresponding inverter that is able to convert the DC current from the PV into AC current that can be fed into your house grid. Inverters come in power conversion capacities. They range from 1 to 3 to 5.5kW single phase and 5 to 30kW for 3 phase. 

 

If you look at the above diagram, you can actually connect the inverters in parallel which allows you to add inverters as you add more PV panels thereby increasing your power generating/conversion capacity.

However it is important that the inverter that you selected allows for parallel connections (they call it smart inverters) in order for this to work. So you can start off with say a 3kW inverter and 6-7 PV panels, and in the future if required add another inverter (could be another 3kW or even a 5kW it doesn't matter) and then add the required amount of PV panels to get 6 - 8kW. In fact you can add on as much inverters as you want as long as the system permits.

The advantage of this is it allows you to increase your power generation in the future as you see fit. The additional inverter(s) also acts as a redundancy, if 1 fails you still have another 1 running albeit with a lowered capacity.

The downside of this is it costs more to purchase 2 x 3kW inverters than it is to purchase 1 x 5.5kW inverter. 2 x 3kW inverters would cost around 7,000 - 8,000 baht more than a 1x 5.5kW. There is also the cost of additional wirings and the additional space on the wall that you will need to allocate for it.

Or you can get 1 x 5.5kW inverter and start with 6-7 PV panels to get 3kW and then add on in the future until you max out your inverter capacity.

 

[Noble_Design]

Protecting your Investment & Misc. 

 

The last bit of information that I would want to share is related to the circuit breakers and surge protectors that are required to protect your PV system. But before that make sure that your installer has run a grounding wire for the PV panels. Since those panels are way up on the roof they are susceptible to lightning strike and you want to divert as much as those charge into the ground rather than into the inverter.

These are the lists of circuit breakers and surge protectors, you will need both since breakers will only protect wires from starting a fire due from too many amps, whereas surge protectors protect your appliances from power surges, which is a brief spike in voltage.

1) Beside the grounding mentioned earlier, there will be a breaker and surge protector between the PV panels & inverter to protect against lightning strikes.

2) If your system has a battery like mine then you will need a breaker between it and the inverter incase there are shorts on either one that creates a power surge.

3) There's also a breaker and surge protector between the grid (PEA) and the inverter.

4) And finally there's a breaker+surge between inverter and your house's breaker.

[Marc26]

Very informative ND, thank you