hi, how does this calculation work? multiply by 4 then multiply by 18? Aircond multiply by 16?

Those are hours of usage and number of desktop/laptop stated by the origin question.

Electricity bill is calculated in power aka KWH, now is about 30+ cents per KWH

So if your equipment consume 100W and you use it for 10 hours then, 10 x 100 = 1KWH.

Don't mind share on calculation of air cond. consumption(average for 1HP, 1 1/2HP & 2HP)

Averagely how many watt air cond. consumes?

Both has pros and cons.

Central:
1) Takes longer time to boil / keep warm -> more electricity
2) Provide continous steady stream of warm water. You don't bath in hot water Hot water is to process dressed-chicken.

Individual:
1) Almost immediate warm water. Sometimes too hot and boil off the sausage/fish-ball/double-pau
2) Irregular temperature, fluctuate. Which will make you turn the heater up. Then... refer #1

Best is, install another separate tank on top of the roof, either black PVC or metal is fine, as both absorb heat. Let our natural sun become the heater.


Unless most of your team take bath at similiar time, otherwise don't go for central.

Another way to look at it, you don't use a 5L kettle to boil water, then make a cup of 50ml espresso. It would be better to use the small 1.2L jug to boil and faster too. Save electricity.

Unless you plan to boil 5L water, then make 2-3L of hot coffee/tea for a gang.

Good analysis. I was thinking of putting the water tank to expose to the hot sun, but am worried whether it will be warm enough for the evening. Also, then when you want cold shower, you can't have it. Again, I don't think people take cold shower these days.

In scientific term 1HP = 0.75KW.

But for actual case and actual consumption, it could varies from manufacturer to manufacturer, depended how the motor setup etc issue.

There is no straight accurate answer can be given.

Just a rough guide only.

The tank on roof will provide warm water on sunny days and if bath around 5pm-8pm. If water not warm enough (e.g. you always come home 11pm) or on rainy days, I suggest use individual heater if really want to. There are other consideration as well, low water pressure, need pump? Extra tank on roof use same piping or new piping ? cost ?

If want cold shower, one way is to buy a small crushed-marble/white-plaster tank. Old fashion type. Not plastic/white-PVC. Use the small-bucket (cedok) method. But must fill it up with water in advance 3-5 hours. Marble (like marble flooring) will cool down the water. To double/triple up the functionality, you can also use it to flush toilet or rear some fish/tortoise in it

It may sound impracticle or ugly though... depending on preference for greener world or look nice/design. E.g. wear coat/jacket + tie walk outside the sun at klcc. Sure look proper and smart, but sweat like an idiot.

Side track: I don't like those designer/architect who build full length glass wall/window for homes. It is just plain stupid to have the sun shining, and you pull the curtain to cover it. The heat build-up will require more air-cond. Yeah yeah, it look nice, but impracticle. If we're living in Scandinavia, then full length glass is alright. But no, not here in M'sia with 4 seasons of summer.

So the cost of electricity supply for 1HP for 8 hours is

0.75KW x 8Hr x RM0.30/KWH = RM1.80 (If TNB supply rate is RM0.30 KWH)

In a month the cost of electricity is RM54.00 for 1 1HP air cond.

If 3 nos of 1HP air cond the total cost of electricity is RM162.00


Therefore if i insulate my house and use only 2 hrs per night the savings would be

0.75KW x 6Hr x RM0.30/KWH x 30 Days x 3 nos of air cond. = RM121.50

Is my calculation correct ?

OK will go to my design board and try to be green & nice.

I do agree w/ you. We malaysian like to have many windows, but we almost never use the windows feature, as they are always covered up by curtains!! So, what is the point? I would rather design to have glass panel at the 7' height, where you get privacy & light!

Not that high lah. TNB charge you 200kwh for 0.218. And the rest is 0.334. All state in your bill. 1hp don't use that much power. My 1.5hp only cost me rm20-30/mth. Saving depend on your aircon type and aircon setting and the room sealing.

I don't think insulate can reduce that much. You still on your aircon 8hr but the comp will run lesser since the cold air can keep longer.

Only rm20-30/mth?? How long do you on everynight. Something wrong with your TNB meter?

Why my bill so high ? Close to RM400.00 per month.

I thought air cond. is the main culprit. How to cut down?

I hope my TNB meter got problem. Everynight 7-9hr.

Buy aircon according to your room size not your wallet size.

How do work out the capacity of air cond. required? I often heard of BTU and did ask about it here. I was informed it refers to British Thermal Unit only.

May be you can help. Can teach aah!

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Added on August 13, 2009, 4:36 pm@Ozak said his 1.5HP don't consume that much.

Are your calculation correct?

Say 25cent per hr . A night 8 hrs equals RM2 per night.

Now who is right now - cherroy or ozak ?

This post has been edited by Calmman: Aug 13 2009, 04:36 PM

Lazy to repeat. Just read back few pages and the aircon thread here. You will get the answer.

The calculation is correct. Just the usage and aircon is vary with each house. As cherroy said, there is no straight accurate answer can be given.

My setting is 1.5hp inverter, well ventilate outdoor unit, temp at 25deg and everything in auto to optimise the saving. Seal all the hole that might probally cold air escape.

I read thro' the last few pages, nothing about room size vs air cond. capacity.

You all talk more on air cond inverter and cable size. I think changing size of cables for the house will cause a bomb. A lot of hacking works......not viable

Accidently found your post, your first 1HP bill RM100+ and change to inverter 1.5HP now bill RM65+......

Now you said Rm20-30/mth

He..He....you are pulling our legs.

That is my total whole house consumption bill. Only the aircon is rm20-30. TNB bill never itemise the bill.

Adalah. Check the aircon thread.

This post has been edited by ozak: Aug 13 2009, 05:37 PM

Whole house bill only.....RM65+ ........don't buy TNB share....where got profit?

Your other electrical goods only consumed RM30+ ????? I can confirm your TNB meter something wrong.........

Don't reveal ur address.....serious offence.

Yes. I always find a way to reduce the consumption. Keep on looking power saving and energy star goods. I calculate the saving before buy some electrical thing.

Why you can consume that much power? Everything big and power hungry things?

Don't reveal ur address.....serious offence. --->???

This post has been edited by ozak: Aug 13 2009, 06:02 PM

Hi cloud9_lee, u hv not informed me if your house is facing west?

My side wall is facing west, i worry if install the material on ceiling make no much difference since the heat from the side wall is not being taken care.

I saw a device being sold at a booth in Tesco which claim to save your electricity bill. Don't know the name. Anyone has this device installed in your house?