Wat Yan Nawa and the use of solar energy

BANGKOK: -- Wat Yan Nawa is the first temple in Bangkok which has turned to solar cells as a source of alternative energy source to save power bills. It also hopes to set an example for other temples to follow on its foot step.

At an investment cost of about 1.4 million baht, 96 solar cell panels were installed on top of the Mahajesada building on the compound of Wat Yan Nawa. Energy produced from the panels will do directly to the invertors or transformers which will turn the direct current into alternating current for household use.

Although traditional electricity source is still being used in the temple, the use of solar energy has saved the temple about 20,000 baht in electricity bill each month, said Phra Promvachirayarn, abbot of the temple.

Phra Khru Wimonpanyakhun, abbot of Wat Pa Srisaengtham in Ubon Ratchathani, said that the 96 solar cell panels produce about 27 kilowatt of energy or 120 units each day. This, he said, has slashed about 20,000 baht from normal power cost of 300,000 baht per month.

While admitting that initial investment cost is high, Phra Promvachirayarn said that, in the long run, solar energy is worth the investment.

Source: http://englishnews.thaipbs.or.th/wat-yan-nawa-and-the-use-of-solar-energy


-- Thai PBS 2015-11-27

The converters use about 20% of the energy needed for the 12V DC to 220V AC conversion! If they would use a 12 V DC system for the lights then they would be able to save even more as there would be no need to convert the energy. We are running 12 streetlights in a 12V system and our solar cell is only 80W that charges two 80Ah deep cycle battery. So far it has run for 6 months without problem. So if they would only use the converters for such things that are expensive/impossible to buy in 12V versions then they could save a lot more.

They are called inverters. You are ignoring voltage drop over any reasonable distance and required conductor sizing with low voltage DC power supply.

if the figures quoted are correct:

They paid 1,400,000 Baht / $58,000 (Australian) for a 24kW system (96 panels at 250 watts)

The solar power generated saved 20,000 Baht in one month; that's 667 baht a day / AUD$27.80 / $5.56 a kilowatt?

The same system (actually a 25kW) in Australia (before rebate) would cost 1.200,000 baht / AUD $50,000

and based on 5 peak sun hours a day, provide 125kw

How many years until they start saving money after spending 1.4 million baht? Why don't they save money by installing energy saving light bulbs. That's my negative side, now positive. Great idea, hope big shopping malls will follow suit and install solar panels on their roofs. The less we spend on natural resources the better. Green energy will help reduce carbon emissions therefore reduce global warming that causes droughts like this years in Thailand.

How can the temple be consuming 300,000 baht a month in electrial usuage? There is something wrong for this figure to even be mentioned as to what the required need of the temple is. That amount of consumption should run about 100 aircons with capacity to cool 100 bedrooms of a size approaching about 4 meter by 4 meter, 24 hours per day.