What is your average electricity bill?

[chopsticks]

Fridge / Freezers are also silent energy guzzlers, not so much because of their power usage (few hundred watts), but because they are on 24/7. If buying new choose one with better insulation and less frills.

[Takiap]

Our monthly bill averages about 1700 baht - no pool and no aircon. Ever since we had our place built, I've focused on planting trees in exactly the right places in order to block out the sun, and even I'm amazed at just how effective this has been. Even on the warmest of day, with the windows open, a fan or two is more than enough to keep the house comfortably cool. At night we even sleep with a duvet.

Of course there is also the possibility that I've simply adapted to the climate here after all these years.

[hhfarang]

^ Do you have a thermometer in the house... I'd like to know what you consider comfortably cool... that would have to be 25c (maximum) or preferably less for me. I can set the aircon on 26 or 27 but then I still have to have a fan in addition blowing on me all the time. Right now, these cloudy and rainy days, the fan seems to be enough though during most of the day, but to sleep well, I need aircon (set at 26c) and two fans; a ceiling fan over the bed and a floor fan blowing up my side of the bed, both at the highest speed. I sleep buff and only under one sheet (while the missus is under enough quilting to sleep outside in the snow in Alaska for me ).

[Nereus]

It is 3-phase power, and yet when the air-cons switch on, the lights go off momentarily. My UPS on my computer kicks-in too, meaning that the power is simply insufficient.

It is not the fact that it is a 3 phase supply that is causing that problem. It is severe "voltage drop" and the two likely causes are 1: the PEA supply transformer is not of sufficient capacity (KVA), and 2: the cabling, both yours and / or the PEA, is not of sufficient size, or is a very long run from the transformer, or a combination of both. Usually, it turns out to be the PEA transformer being too small, and as the developments keep expanding it gets worse.

Are you actually using either a 3 phase supply or 3 phases zoned over the property? I know of very few domestic properties that use anything other than one phase and even less that use phase to phase 380v supply.

It is not necessary to have a 3 phase appliance to warrant having a 3 phase supply. The single phase load should be spread equally around each separate single phase of the 3 phases and the neutral. There are also many, mostly heating type loads such as ovens and hot water heaters that can, and should be, connected across the 380 Volt phase to phase supply.

I think our high bills are because of the 3 phase.......................

The size of your bill has nothing to do with the fact that you have a 3 phase supply. You are paying for Kw hours of energy used. In fact, there should be more use made of 3 phase supplies, as if installed and used correctly, it is more efficient than single phase.

Fridge / Freezers are also silent energy guzzlers, not so much because of their power usage (few hundred watts), but because they are on 24/7. If buying new choose one with better insulation and less frills.

They are plugged in 24 / 7 but do not run continuously. The biggest waste of power with refrigerators, apart from the maid standing there with the door open, is running them only partly loaded, especially freezers. If you do not have enough load in them it pays to put a few bottles of water inside, which once cooled will act as cooling source and reduce the running time.

The following is a rough guide to consumption:

Remember up to 50% of your energy requirements in KWH is consumed by air conditioning.Household appliances 6%, electric hot water systems 12%, refrigeration 20%, lighting 2%, and entertainment (TVs VCRs etc) 10%. (source Ergon Energy Qld. Australia.)

Their web site has some interesting facts on it, including a rough guide for comparison of what different appliances draw:

http://www.ergon.com.au/your-home/save- ... calculator

[chopsticks]

The size of your bill has nothing to do with the fact that you have a 3 phase supply. You are paying for Kw hours of energy used.

They are plugged in 24 / 7 but do not run continuously.

In some countries you pay a higher 'standard charge' or fixed monthly fee for having 3-phase supply as opposed to single phase even if you're not using it. Maybe worth enquiring and downgrading to single phase if it's costing you more and you don't need it.

The compressor inside a fridge/freezer should be cycling and not run non-stop but most do consume power 24/7 due to the defrost heating elements operating when the compressor is off.

[Nereus]

The compressor inside a fridge/freezer should be cycling and not run non-stop but most do consume power 24/7 due to the defrost heating elements operating when the compressor is off.

Not necessarily, it depends on the type of defrosting system. There are two common types of defrost systems. One type uses heating elements and the other type hot gas from the compressor. In either case they they should not run more than 15 to 20 minutes a couple of times a day.

The other more efficient type is "frost free", where because the evaporator is not inside the cabinet, it automatically defrosts while the compressor is stopped.

[Nereus]

In some countries you pay a higher 'standard charge' or fixed monthly fee for having 3-phase supply as opposed to single phase even if you're not using it. Maybe worth enquiring and downgrading to single phase if it's costing you more and you don't need it

.

Yes, that is correct and I do not know what the case is in Thailand. But it does cost more to both install and get 3 phase connected. You can not simply "downgrade" a 3 phase installation to single phase. It would require a completely new cable installation from the PEA supply into the building, just for a start.

[hhfarang]

I believe there is a (large) surcharge here on my monthly bill because I have 3 phase, plus I was required to buy a transformer for the electric company so that I could get it when I built my home which cost 250k baht along with a few poles.

However, I was told by several "experts" including the people from the electric company that I needed 3 phase for the number of electrical "appliances" I would have and because of the size of the home.

[Super Joe]

However, I was told by several "experts" including the people from the electric company that I needed 3 phase for the number of electrical "appliances" I would have and because of the size of the home.

I wouldn't pay much attention to any specific resoning they gave you hhf, as even 'professional bodies' here lie like children to get what they want, but they could well have been correct (or not) that your house would benefit from a 3-phase supply depending on the configuration from their mains supplies. The neccessity for you to have 3-phase is only there due to them not providing sufficient supply, but that's the way it is in such countries. IMO they done you a big favour, particularly in the area you are which is/was fast developing with serious residential expansion. It's a selling point also so not really a waste of money altogether.

I have always opted for 3-phase and even gone so far as to put it in over 40 houses for customers at our own expense because it's better to be safe than sorry imo, you could be experiencing all sorts of issues now if you had opted to 'tag' on the end of the low hanging LV supplies that now have far too many properties sucking juice from it than it is sized/rated for. Whereas if you are entering the back end of a tranny (ofcourse that was intended) directly from the 11kv/22kv MV supplies way up above the local LV supplies then you should be ok generally speaking. To me it's not about single phase or 3-phase but about bypassing the local, and often overloaded, supplies and tapping directly into sufficient supplies.

I believe there is a (large) surcharge here on my monthly bill because I have 3 phase, plus I was required to buy a transformer for the electric company so that I could get it when I built my home which cost 250k baht along with a few poles.

You should have been buying it for yourself rather than the electric company (apart from the point of view that you're buying it because they are not providing sufficient service), is it not on your land? Our always have been.
What do you mean by a 'surcharge'? in your rate being higher per unit (easy to check), or your meter spins round faster than next doors


SJ

[Nereus]

Whereas if you are entering the back end of a tranny (ofcourse that was intended) directly from the 11kv/22kv MV supplies way up above the local LV supplies then you should be ok generally speaking.

Not sure what you are trying to say here SJ, but the 3 phase supply is from the same overhead cabling as the single phase. It is not possible to enter the tranny from the "back end", that would give you the same 11Kv / 22Kv, or what ever the HV supply voltage is.

The secondary side of the transformer is connected in a configuration called "star" or "Y", where each of the ends of the "legs" of the "Y" are one single phase, and the centre of the "Y" is called the "Star Point". Each single phase is referenced from the end of one leg to the star point, which gives you the approximately 220 Volt single phase. The voltage across each end and between each phase leg is around 380 Volts, and this is where any appliance requiring 3 phase is connected. All the single phase circuits have to be connected from one phase leg to the neutral, and balanced as far as possible across the 3 phases.

The neccessity for you to have 3-phase is only there due to them not providing sufficient supply...............

No, it is done to try and provide a more balanced load on the supply lines for one thing, and for another to reduce the size of the incoming cables, and also the "voltage drop" on the line. The supply authority should do a load analysis on the property before it is decided whether or not 3 phases need to be run into the building, unless of course, the customer has 3 phase appliances. It is in this area of doing an analysis that they fall down. The people left to decide just do not know how to, and the ones that do know are probably too busy on the golf course.

[hhfarang]

Ok, about the surcharge... seems something has changed recently. If I look at a bill a few months old the actual usage is 6756 baht and there is a surcharge following that (no translator nearby at the moment, but this added figure has some Thai letters followed by FT next to it) of 1828 baht (then also the 7% tax added, 601 baht) for a grand total of over 9k. This was the usual figures I saw on my bill, always with this surcharge or whatever of a couple of thousand baht (varied with the amount of usage).

However, I just looked at my most recent bill and that same charge (first time I've ever noticed this!) is actually a negative figure! My usage was 8031 baht and what I always thought was some kind of surcharge is -125b making the bill (after tax) actually lower (8459b) than the earlier one, even though my actual usage on this one was 1700 baht more.

About the transformer, no, it was not installed on my land but one pole down away from my house on public land and I was told that I could not own it and that after 90 days (from installation) it would be available for other homes in the neighborhood to tie into. As mine was nearly the first completed home in an area of mostly empty hillside, I didn't think much of it but now there are lots of others, many probably getting the use of the transformer (and poles) I bought but our supply is stable so no worries yet... and the big developments that have sprung up in the area now have provided their own (much bigger) transformers so I guess anyone using the one I paid for are only the "lone wolf" houses nearby.

[Nereus]

(no translator nearby at the moment, but this added figure has some Thai letters followed by FT next to it)

The "FT" is fuel tax, and varies from time to time depending on the the price of oil. Why it is negative I have no idea, except to say that it MAY be an adjustment from an overcharge on the previous account.

[Super Joe]

Not sure what you are trying to say here SJ, but the 3 phase supply is from the same overhead cabling as the single phase. It is not possible to enter the tranny from the "back end", that would give you the same 11Kv / 22Kv, or what ever the HV supply voltage is.

You're interpreting this too literally from a technical point of view Nereus as it was your career, 'entering the back end of a tranny' was a pun as I said in brackets, so sorry for the confusion that was my fault for 'trying' to be funny!! But this is what I mean by being better of from a stable supply point of view by coming directly from the MV supplies and having your own dedicated transformer, that is sized correctly for your property (and future expansion to it), and that no-one else can connect into at a later date. You own it and it's on your property, although for whatever reason HHF's wasn't put on his land.
This obviously makes the assumption that the 11kv or 22kv MV supplies are sufficient, but we've installed in 5 different locations over last 7 years and none have had any supply instability, only shutdowns for PEA works, whereas people in the road on 'the end' of LV supplies have all sorts of problems come early evening time.

No, it is done to try and provide a more balanced load on the supply lines for one thing, and for another to reduce the size of the incoming cables, and also the "voltage drop" on the line. The supply authority should do a load analysis on the property before it is decided whether or not 3 phases need to be run into the building, unless of course, the customer has 3 phase appliances. It is in this area of doing an analysis that they fall down. The people left to decide just do not know how to, and the ones that do know are probably too busy on the golf course.

No I didn't mean the practical reasons for deciding on 3-phase over single phase, I mean't the reason they often (not always, think it depends on whch manager you're dealing with in there) want all the farang single houses/developments to be buying their own transformers and tapping in directly to the MV supplies is so you pay for it and they don't when they have insufficient LV supplies installed, plus they make a 50% mark up on it. Briliant huh!?

I'm not convinced they actually do calculate many houses and make an informed judgement on whether you need 3-phase or not as you rightly say they should be doing. They've made the decision for 3-phase with us before on unfinished small'ish bungalows without asking what equipment would be going in!?


SJ

[chopsticks]

Is there any ballpark figure as to when 3-phase is advisable eg. the possibility of exceeding 60 Amps on a single phase ?
I would guess that having 4+ air-cons, electric oven, hob, pool pumps, water and shower heaters would be approaching the limit for single phase especially if they're all on at the same time !!

[Super Joe]

About the transformer, no, it was not installed on my land but one pole down away from my house on public land and I was told that I could not own it and that after 90 days (from installation) it would be available for other homes in the neighborhood to tie into. As mine was nearly the first completed home in an area of mostly empty hillside, I didn't think much of it but now there are lots of others, many probably getting the use of the transformer (and poles) I bought but our supply is stable so no worries yet

That's strange as so far all 5 have been located on the land and therefore 'private', but we've always had the same manager/engineer in the PEA deal with us. Ironically the first one we had installed we didn't want it on theland but across the road cos they're damn ugly, but he refused point blank despite incentives being offered. Glad he did now really. Be interesting to know what others have exeprienced. One possibility with yours is that some 'cost sharing' occurred with developer/builder and PEA (but not you unfortunately), but purely guesswork.


SJ