Thinking of Solar Power, someone who can help me? How many kW do I need?

[Paul944]

It will not save you money. The most economical is:

You own a house and you do not plan to move next 10 or more years.

You are allowed a grid tied system.

If meter run back is possible take a capacity that matches your monthly average use.

If meter run back is not possible you can take a smaller system that closely covers your day time power usage.

In the Netherlands a system that delivers 3200kWh a year covering 22 m2 roof (35 degrees angle) costs about 200,000 baht (excl. installation).

The same system will produce more in Thailand and will be a bit cheaper, probably 200,000 with installation costs.

Still it will take about 15 years to reach the break even point if the meter can not be run back during the day.

[Feesbay John]

It will not save you money. The most economical is:

You own a house and you do not plan to move next 10 or more years.

You are allowed a grid tied system.

If meter run back is possible take a capacity that matches your monthly average use.

If meter run back is not possible you can take a smaller system that closely covers your day time power usage.

In the Netherlands a system that delivers 3200kWh a year covering 22 m2 roof (35 degrees angle) costs about 200,000 baht (excl. installation).

The same system will produce more in Thailand and will be a bit cheaper, probably 200,000 with installation costs.

Still it will take about 15 years to reach the break even point if the meter can not be run back during the day.

The only meters that do not run backwards are the digital meters, all others do which is 95% in Thailand. Yes solar has come down in price over the last few years. Its come down to 40% of what it was 3 years ago.

I don't know what setup you have in Netherlands BUT that sounds like a 1.5kw setup. We do a 2.8kw setup for around 148,000 baht installed, average 15.5kw per day x 365 = 56,574kw per year. This setup will save you around 2,000 baht per month, Payback time around 6. 2 years.

[Feesbay John]

Why do people keep mixing the Grid Tie and Inverter together. These are 2 different things. The attachment is only for a Grid Tie, It doe's not mention anything about a battery bank or inverter.

Grid Tie,

Takes the power from the solar panels and feeds it into your system.

The size off the Grid Tie doe's not matter to what you can run in your home, it only matter's to how much you are looking at saving each month.

A Grid Tie doe's not power your appliances, it only supply's power to your grid.

Depending on your solar size will depend on how much power and credit you will have for the night time.

Your meter is like your battery bank in the sense off it will turn backwards in the day, given you credit for the night time.

Look at the attachment and work out how much it will cost and how much you will save, this is around the amount of cost and saving's.

UPS Inverter and a battery bank.

This is for people that have no mains, poor mains supply.or just need a backup system.

Depending on what you need to run will depend on the battery bank size and the inverter size.

This is completely different from a Grid Tie and should never be run together. Unless you have a hybrid Grid Tie which can be run together.

Setting a solar system up is one off the main things that has to be right. The panels have to be married to the Grid Tie and the Grid Tie to them. If this is not done right it can take you 3 times longer to get your money back. Example is in the attachment here. Panels setup wrong, Grid Tie not married to the panels, meter did not go backwards, BUT now after setup right the meter is turning backwards. If the roof is not south facing the panel setup is very imported. This was setup by a Solar company in Bangkok, don't ask for there name as I will not give it.

If anyone would like to see this setup our customer is more than happy to show you. This is in Kanchanaburi.

Seeing as you're obviously involved in Ping Solar, can you please advise what's needed to implement a grid-tie system in Thailand, if you're not part of the official Solar Rooftop program?

i.e. What permits are needed? are there any duties to notify the PEA/MEA? Must you use only grid-tie inverters that a pre-approved by the PEA/MEA? Are there any inspections/approvals required before commissioning? etc.

Yes I am joint partner in Ping Solar with my wife. There is ways around the rooftop program if you just want to use for yourself. As we are a business we do not want to give away our trade secrets. There is people you have to notify within 60 days off install and we let all our customers know how and what to do.

[trogers]

Cheaper to set the air-conditioners to 27C and use fans.

[mccw]

The systems in your picture are all grid tied with no batteries?

There for you still use the grid in the night time and any extra/ unused power from day time is basically wasted.

A 5KW system I just had quoted for my house; with batteries; 450k bht.

Grid tied too so if I use over my available power amount I can still suck from the grid if needs be; like aircons at hight of hot season. But if grid goes down I can adapt use age to with in the available and keep critical systems running indefinitely - like fridges, freezer, fans and a few lights.

My purpose is for sustainability's and preparedness rather than financial but according to the company I should recoup my money from bills savings after 6 to 8 years.

The guys said aircon sucks a lot of power and best not to use if grids gone down to be safe side. That indicates to me that in reality you may struggle to eliminate your bill from a 5 KW system even if you do have batteries to see you through the night time.

Your aircon use is really high for such a low bill; I use mine only in the night time and get bills of around 4500; I'd have thought with your use the bill be closer to 10 thousand. Maybe my aircon is older and less efficient or something.

Good thing to be independent supply anyway I think.

I'd say start off with 5KW and see how it goes.

Good luck

[namdocmai]

[namdocmai]

[namdocmai]

I also have been searching for ways to build a solarpowered airconditioner.

But to use aircon at night my plan is to let the system cool water which is stored in a big isolated tank. At night it can be pumped out for cooling.

It can also be a compressed gas system that stores energy for at night.

If i had my own watersource i would use that water to cool the house and pump it back into the soil after use.

There are many more ways to cool a house.

[Crossy]

The systems in your picture are all grid tied with no batteries?

There for you still use the grid in the night time and any extra/ unused power from day time is basically wasted.

This statement is untrue, a grid-tie system will spin a regular meter backwards when exporting power, so you are effectively storing energy in the grid.

Agree that a degree of independence is nice, a truly hybrid system gives the best of both worlds.

[trogers]

I also have been searching for ways to build a solarpowered airconditioner.

But to use aircon at night my plan is to let the system cool water which is stored in a big isolated tank. At night it can be pumped out for cooling.

It can also be a compressed gas system that stores energy for at night.

If i had my own watersource i would use that water to cool the house and pump it back into the soil after use.

There are many more ways to cool a house.

Does the small difference in temperature make this viable?

[Somtamme]

Remember power generation by convention is rated as kilowatts per hour and therefore, your demand should to be matched appropriately, after you have explored options to minimise consumption first.

Also, a 5kW PV array can be very expensive, whereas a small solar water heater can be much more cost effective (BHT per kW).

[Somtamme]

Sorry, to answer your question;

Based on unit price per kW @ 4.5 BHT and your monthly bill BHT4,500 this equates to a monthly power demand of about 1000 kW or on a daily basis around 30kW (1000/30). This is less than earlier respondent.

Power ratings of PV panels are based on kWhr, so a 10 kWhr array if producing this power over 5 hrs sunshine should exceed your required daily demand. However, even considering variability in the weather and fluctuating demands, it can be seen that a 10kW array may be larger than your needs. The only real way of showing this is from meter readings after installation, so ask for references from other installations. Remember, it is in the engineers interest to over-sell their products to maximise profits.

[namdocmai]

I also have been searching for ways to build a solarpowered airconditioner.

But to use aircon at night my plan is to let the system cool water which is stored in a big isolated tank. At night it can be pumped out for cooling.

It can also be a compressed gas system that stores energy for at night.

If i had my own watersource i would use that water to cool the house and pump it back into the soil after use.

There are many more ways to cool a house.

Does the small difference in temperature make this viable?

I have no idea how much the temperature difference is. Not many thai houses have a basement but the water in my shower that comes out first is always cooler then the water after 10 seconds. That means it is cooled while being in the pipeline under my house.

Maybe 5-10-30 meter deeper in the soil it is much cooler? What temperature is the water from a waterwell?

You don't need a very high difference in temp. but then a lot of water is needed. Those systems pump up cold/warm water but also pump it back 10-20 metre away from where it is pumped up.

In the caves in thailand it is a nice cool temp. That can be used to cool a house. You can have a small solarpanel, a waterpump and a fan/radiator and the aircon is working on solarpower. At night it still works on the grid.

I think it's possible to build a house in thailand where it is always 22-25 celcius. Just the right design of house, isolation and a solarpowered coolingsystem.

[mccw]

You could always bury your house I suppose.

So nice and cool.

Build it in to a hill side perhaps. Like a missile silo or bomb shelter

[namdocmai]

You could always bury your house I suppose.

So nice and cool.

Build it in to a hill side perhaps. Like a missile silo or bomb shelter

Well that probably will also work well, and then grow some big tree's on top.

I think a 20 cm pipe which is buried deep under the house can be used as a free supply of cooled air. It will be availlable unlimited. That combined with an insulated house and much shade will help a lot.

It seems nobody in thailand is interested in developing cooler houses or buildings. All inventions have to be done abroad.

[mccw]

You could always bury your house I suppose.

So nice and cool.

Build it in to a hill side perhaps. Like a missile silo or bomb shelter

Well that probably will also work well, and then grow some big tree's on top.

I think a 20 cm pipe which is buried deep under the house can be used as a free supply of cooled air. It will be availlable unlimited. That combined with an insulated house and much shade will help a lot.

It seems nobody in thailand is interested in developing cooler houses or buildings. All inventions have to be done abroad.

Actually in Thailand there are many Eco housing builds and designs. Several universities cover it in their sustainability courses. The professors contract to build / design the Eco buildings.

I think the lack of general usage is down to cost; most Thai just want a roof of their own before worry about insulation and all that. It would be the same in the west generally unless the governments hadn't instituted Eco standards regulations. And now it's mean the costs are so high for building in UK for example that there is a massive housing shortage. Country like Spain with hardly any regs has tooooooo much housing, but still many the locals can't afford it and half the youth are out of work.

Thailand is doing ok in my view.

Free market keeping costs down and letting people to own a home is a good start. Can upgrade later.

[Somtamme]

You could always bury your house I suppose.

So nice and cool.

Build it in to a hill side perhaps. Like a missile silo or bomb shelter

Well that probably will also work well, and then grow some big tree's on top.

I think a 20 cm pipe which is buried deep under the house can be used as a free supply of cooled air. It will be availlable unlimited. That combined with an insulated house and much shade will help a lot.

It seems nobody in thailand is interested in developing cooler houses or buildings. All inventions have to be done abroad.

Actually in Thailand there are many Eco housing builds and designs. Several universities cover it in their sustainability courses. The professors contract to build / design the Eco buildings.

I think the lack of general usage is down to cost; most Thai just want a roof of their own before worry about insulation and all that. It would be the same in the west generally unless the governments hadn't instituted Eco standards regulations. And now it's mean the costs are so high for building in UK for example that there is a massive housing shortage. Country like Spain with hardly any regs has tooooooo much housing, but still many the locals can't afford it and half the youth are out of work.

Thailand is doing ok in my view.

Free market keeping costs down and letting people to own a home is a good start. Can upgrade later.

But what is eco. You refer to the West, but Europe is cooler. Code for Sustainable homes in the UK is also being scrapped in favour of the building regulations. Even the building regs are minimum standards. Energy is the number one issue, and therefore it means following the basic premise of reduce the need for this finite resource first. So yes, this means insulating against the extremes of temperature and probably in Thailand of installing some PV and solar panels to reduce long-term bills further.

[Feesbay John]

Sorry, to answer your question;

Based on unit price per kW @ 4.5 BHT and your monthly bill BHT4,500 this equates to a monthly power demand of about 1000 kW or on a daily basis around 30kW (1000/30). This is less than earlier respondent.

Power ratings of PV panels are based on kWhr, so a 10 kWhr array if producing this power over 5 hrs sunshine should exceed your required daily demand. However, even considering variability in the weather and fluctuating demands, it can be seen that a 10kW array may be larger than your needs. The only real way of showing this is from meter readings after installation, so ask for references from other installations. Remember, it is in the engineers interest to over-sell their products to maximise profits.

Here in Thailand we work on a 5.5 system,, so for 1kw of solar will give you 5.5kw on average per day,,, AVERAGE,,, some time more some times less,,, BUT you have to think when it is less you use less electric,,,, So a 30 kw used per day would mean you would need a 5.5kw system,,, We have customers that have to turn on the air con just to use the power they are making,,, Its a 6 to 7 year payback time,,, NOT 10 to 15 as someone said,,, The price off solar has dropped 60% over the last 4 years,,,,