Reducing Costs-Any tips?

[Dave A]

If you turn the thermostat to 70 DC,

The problem I see there is you now have a higher temperature differential which should result in a higher heat loss rate from the geyser.

you use far less hot water when showering or taking a bath, so the geyser does not have to regain all this energy it lost since it still has quite a lot of hot water in vs. ice cold water topping it up. What do you think??

But you're using more energy to bring that water up to your set temperature. Assuming the user is adjusting hot and cold flows to get a particular end temperature, I'd guess the energy you're putting into the system is the same whether you're using a higher or lower hot water base temperature. However, the higher the hot water temperature, the higher the energy losses along the way due to the higher temperature differential to the environment it's passing through.

In a way it's comparable to line resistance loss principles in electrical systems.

[murdock]

i am yet to see proof of any of this energy saving stuff...it is only logical if you use a 1 mm hole in your shower spout instead of a 5 mm hole but if you stand in the shower for 20 minutes how are you saving ...i am busy with 2 customers being told a R100 000.00 power factor correction unit will reduce costs...you have to make sure you are on the correct metering tariff before you do anything and get a harmonic and load profile...if you have a new type electronic meter you can download info straight from the meter.

there is a lot more to energy saving than people think....to start with it is a life style not just a timer in the geyser or reducing the temperature...it all helps.

if you bath 5 times a day and set your geyser to switch on and off in the morning and night you gona have a cold bath during the day...you must see how quickly these timers are bypasssed after the first cold bath your wife has...and setting it down to 55 just means you fill the bath up 20 % more to before you switch to cold water...i am not saying they dont save electricity just pointing out that you need to change the way you do things.

you want save money
switch things off
dont stand in the shower for 20 minutes
put tanks under your gutters
water your garden early evening
use pots which fit on the stove properly
microwave stuff to heat
dont keep opening the fridge door
use electric blankets and under floor heating
close curtains or put blinds on the outside to stop the heat
etc etc etc.
there are just toooo many things to mention.

people will start taking this a lot more seriously when the eskom tariff is increased to an amount which will affect the pocket.

save electricity and energy.

rotary compressors on aircons...fridges...deep freezes etc use less energy electricity than the old type...they have been out for years already.

[murdock]

LED downlights are great if you buy the correct ones...the problem is finding the correct ones...there is a 7 watt phillips unit which works well...try find one...i have even tried contacting phillips themselves no such luck...and again it all about application and position.

i will be installing my 1500 watt light on the side of the house again...purely for security reasons...it lights up the neighbourhood...just dont forget to switch it off...otherwise it doubles the electricity bill.

[Sparks]

You received good replies here, in a nutshell you should defimately go with LED's for your lighting without losing ambience.

Insulating your geysers and hotwater pipes is all you can do there other than connect them in series in which case you can lower your thermostats.

Checking your fridge/freezer thermostats and seals will definately help.

Your guzzlers' are the deep fryers and grillers. A thin bottomed pot with oil no deeper than you require will be cheaper than a 3ph deep fryer to use. You could also go for gas grillers rather than 3ph grillers which I am certain you have.

One last thing have you had someone check your lights to see that there are no earth leakages? That can waste a lot of power and fluorescents often go to earth.

Good luck.

[BBBEE_CompSpec]

I don't insulate a geyser, I insult the geyser. It depends on which geyser you're talking about. My old geyser lives in Cape Town.

On the more serious note, you all need to become like me. Please remember mine is due to Liver damage (I don't drink alcohol or smoke at all). I prefer to lie in the snow. It brings me untold relief. I like cold showers, luke warm baths, drinking my tea/coffee iced cold, drinking my cool-drink room temp.

The reason I moved to Qtn originally was because I can handle the temps up to -15 degrees. The heat, on the other hand in summer is a killer, thus the reason I get out of there for those months. I like the snow, and let me tell you it can snow for up to five months in winter. I walk around the area in winter without a jersey. My prepaid bill, for any month in the year, is around R200-00 and I did a lot of cooking on my health grill. My veggies were done on gas.

That's called cost cutting.

[AndyD]

Something I've always wanted compare but never got the chance....New domestic geysers has a standing loss of around 2.2kW@60DC over a 24hour period. I.e. if you don't open the hot water once, it will cost you 2.2kW...60c/kW...R1.32...30 days around R40. The geyser costs you money if you use hot water.

All geysers will have standing losses according to how effective their insulation is. There's several things that can alter this effectiveness. If the insulation material gets wet either due to the geyser standing outside in the rain / irrigation spray or there's a leaking fitting on top or a leaking cylinder for example then the insulation will not be as effective as it should be.
Everyone should fit a geyser blanket and insulate the first couple of meters of hot and cold pipework. This will pay for itself in a few months of electricity savings.

If you turn the thermostat to 70 DC, you use far less hot water when showering or taking a bath, so the geyser does not have to regain all this energy it lost since it still has quite a lot of hot water in vs. ice cold water topping it up. What do you think??

The work the geyser does would be the same in both cases. It would mak no difference if you heat the larger amount of water to a lower temperature or heat a smaller volume of water to a higher temperature.

The thing that swings it is that the standing losses costs through the cylinder insulation will be far higher if the temperature of the stored water is higher. Set the geyser at 55 Celsius maximum.

Apart from wrapping the geyser in a thermal blanket and sealing off the roof space around the geyser, wrapping the pipes......what do you think about replacing the geyser thermostat with a digital one. Surely the digital thermostat would control the temperature much better over the long run not overshooting and undercontrolling, i.e. saving you money as well? Or is the loss negligeable?

A standard digital thermostat does exactly the same as a mechanical one that's originally supplied with the geyser. The only difference is that it uses an electronic probe to sense temperature. You may be able to achieve a smaller differential with an electronic thermostatcwhich might reduce 'overshooting' but this will mean that the element on/off cycle times will be faster and thermostat wear and tear will be greater, mean failure time will be less.
There are electronic temperature controllers (PID) that are predictive in nature. They look at the speed that the temperature is rising or falling aswell as usage trends and make decisions about whether the element should be 'on' or 'off'. These are expensive, complicated and will only save small amounts of energy in an application such as a domestic geyser.

I heard a while ago someone invented a way to re-use water expelled from the geyser when initially opening it. Where is this technology? Why does is always take years to get something to the public The therory is that there is a pipe flowing from you tap back to the geyser, which is actuated thermally. If you open the hot water tap, you dont want or need the cool initially heated water, so you don't see any water coming out. The water is pushed back into the geyser (luke warm already compared to cold water) and decreasing the energy needed to heat up the water again. Once the water is hot enough to actuate the valve, it slowly switches and you get only hot water (exactly what you wanted). This saves you water and electricity. No real $ value at first, but over a years usage I believe it would definately be worth while.

Feeding the initial cold water from the pipework back into the geyser won't save much electrical energy. This cold water will cost almost the same to reheat as new cold water would cost. It would save water possibly, if you were in the habit of running water to drain until it comes hot, but at the expense of a complex plumbing installation and relatively complicated controls. I've not come across the system you describe but it sounds like it would be more suited to new installations rather than a retrofit option.

Hope this helps
Andy

*EDIT*

Any tips for reducing electricity costs or alternatives? In the restaurants the fridges pull huge power and naturally lights, air con and small appliances. At R20 000 a month and looking like R30 000 thats a whack of cash. Any ideas? Solar power, candles anything I will take it!!!!

Sorry about the double post, I got overexcited and jumped in too quick, I didn't see the OP was about restaurants.

I have profiled the energy consumption of numerous commercial restaurants with a view to cutting consumption and the conclusions are almost always the same.

Diachroic 50 watt downlights have been all the rage for the past few years but they are a killer when it comes to the electricity bill. Some restaurants can have in excess of 150 downlights @ 50 watts each often with inductive transformers. If you're being billed in kVAh then they cost a fortune to run and then some. As mentioned above there are LED alternatives that will fit in the same fittings but often the light output, illumination angles and colour frequency of these can be an issue, not to mention the initial cost of re-lamping. There are also compact fluorescent alternatives you might prefer. Both LED and CFL are available in dimmable models but they're difficult to find and expensive. Sometimes they specify that you must use a leading edge or trailing edge dimmer so try one first before you commit to boxes full of them. Note that most LED and CFL globes (bulbs) are not dimmable, if it doesn't say it's dimmable on the box then assume it isn't until proven otherwise. Another word of warning, the cheaper LED lamps with multiple LED's inside them run multiple LED arrangement on a single internal driver which over drives the remaining LED's when the first one goes down so complete failure rapidly follows. Stick to recognised brand names even if they are double the price.

Air conditioning costs a fortune to run, make sure it's turned off overnight. If you have large open doorways to outside areas then install air curtains to keep the cold in and the heat out. Finally the kitchen has an extraction hood that sucks out large quantities of air. If you don't have a supply air system installed to replace this air back into the kitchen then you will be sucking out the airconditioned air from your restaurant. You should have fresh air supplied back into the kitchen to he tune of 90% of the extracted air. (The 10% difference is to keep the kitchen at negative pressure for fire safety purposes.)

Refrigeration costs can be reduced. Make sure that all fridge and freezer doors close properly and the latches work. Keep the door seals in good condition and replace them sooner rather than later if they're damaged. If you have a freezer room then get the defrost cycles optimized. Only use glass dorr fridges if you really need them, if you have them make sure the fluorescent lighting tubes inside them are in polycarbonate sleeves. Empty all under-bar and display fridges into the coldroom at night and switch them off. This can also make a morning stock take easier and improve FIFO procedures.

Insulate geysers and put them on timer clocks.

Stop sloppy procedures like staff using running hot water to defrost food. We've seen this on several occasions and apart from being in breach of HACCP regulations they will empty several geysers of hot water to defrost one box of fish.

Install the push button type taps in the bathrooms, they're more hygienic and stop kids leaving them on.

Make sure extract canopy and supply air fans and air-con switch off at night.

Optimise your morning switch-on and night time switch-off procedures for the kitchen equipment.

Don't leave the restaurant lighting on overnight as security lighting.If you need lights at night install a more efficient option.

Unfortunately solar and other alternative or renewable energy systems aren't a practical option for commercial restaurants at the moment.

[Sunfor]

Any tips for reducing electricity costs or alternatives? In the restaurants the fridges pull huge power and naturally lights, air con and small appliances. At R20 000 a month and looking like R30 000 thats a whack of cash. Any ideas? Solar power, candles anything I will take it!!!!

Hi, lighting is always your first point of entry to reduce energy as heating and cooling ar more costly to address.
shannon