Low-Wattage consumer appliances

[morg]

Hi there,

I'm trying to find the best examples of energy efficient consumer appliances for developing world (limited power) applications.

I'm looking for the lowest wattage irons, kettles, fridges, fans, washing machines, TV's and music systems.

Specifically irons ... wattage is a problem in many of the areas I work. Has anyone ever heard of a 'slow-charge' iron that perhaps consumes a similar amount of power overall but draws a lower current ? Or some new technology I'm missing ...

I dunno .. any links to interesting products or comparative studies you've seen would be a great help.


Thanks,

Morgan.

 

[HiTech]

From what I gather, appliances that wear the Energy Star tag are considered to be quite efficient at what they do, as well as environmentally friendly. Just look for this symbol:
**broken link removed**
However, you do state that you are looking for the "lowest wattage" which often equates to smaller sized appliances, if that's of any concern. I can assure you that the Energy Star rating is effective and from my recent move to a new home, I purchased all of my appliances with that spec in mind. I have saved a noticable amount of monthly operating costs as compared to my former appliances that were not ES rated.

 

[audioguru]

If you reduce the amount of current used by an electrical appliance that heats, like an iron or kettle, then it won't get as hot or it will take a longer time to heat. If electrical power is limited (this is nearly the year 2007, not 1707) then use a fire for heat.

A fridge, fan and washing machine won't work well with a lower current.
A TV won't be bright and a stereo won't be loud.

 

[Hero999]

To save energy, don't fill your kettle all the way if you're just making one cup of tea, turn the volume down on the TV and stereo, was clothes at a lower temperature, it's all pretty obvious really.

 

[raedbenz]

everything depends on the material quality of the heated body itself..
u can ask some appliances stores for the energy classes of each equipment.
there is class A,B,C etc....if u go over the deep details u might get benefit..

 

[djtaylor1]

One thought, you mention "developing world" which often means hot areas and plenty of sun.

Have you thought about solar water heating for some of the jobs?

Why boil ambient temperature water when you could boil already solar heated and in fact some of the solar panels are claiming very high temperatures already so you're pretty much there with the energy input for the rest.

Similarly, for the washing machine, use solar heated water to begin with so the heating cycle isn't actually required. My washing machine is already an energy efficient appliance but it's a cold fill only. The rational being that such appliances are usually remote from the hot water tank and the amount of water it uses won't draw enough to even pull hot water. However, if you can control this distance, you might be able to provide an already hot fill given that wash temperatures can be 30 to 40 degrees. You could easily provide solar heated water above these temperatures. It's the heating that consumes most of the power.

David.

 

[morg]

Thanks all.

DJTAYLOR: Thanks, that's a good suggestion. I believe solar heating is being done in the villages I'm working on, but not formally and not as part of a system involving a washing machine or kettle. I guess if I was to disconnect or limit the heating elements I could ensure a lower rating.

Sorry, if this sounds a bit strange I haven't explained the context fully. I have another post https://www.electro-tech-online.com/threads/developing-world-electricity-concepts.26100/#post181834 - that gives a good background for anyone interested.

Many off-grid households around the world are running on village mini-grid, or solar panel home systems where the available wattage is between 200 - 700W. Western products clearly aren't designed for this limitation but are often the cheapest option due to the economies of scale. I'm looking at what's out there to try and make recommendations.

Irons are a much requested item. In this context the iron cannot be permitted to draw over 700W or so, but users would wait longer for it to 'charge' if this were possible. It's unlikely there is such a product, I know -
Battery storage with an inverter is one electrical solution. I just wondered whether there was a thermal storage solution that could accumulate heat at a lower wattage. I'll need to get the thermodynamics book out.

 

[Oznog]

The more important thing is actually the idle power. For example, the bad ones ("energy vampires") might be a stereo that when you press the remote button to turn it off, it may power down the amplifier section but still draw 10W of power. Or it may even want to stay "warm" and turning it off does next to nothing to reduce its power consumption. Even a simple "wall wart" power transformer with nothing plugged into it may still draw half a watt.

People running solar deal with this issue all the time. A couple of VCRs and TVs turned off, some transformers plugged in, etc 24 hrs a day can actually use a great deal of the panel's overall capacity for a guy who initially calculated running a tv for an hour and a couple of lights through the night, maybe a power tool every few days. Most people leave dozens and dozens of things plugged in all the time and it really adds up!

These guys usually just unplug unused devices. It helps to have devices which will work right away when plugged back in. For example, it's really annoying when your VCR and microwave blink 12:00. More annoying if it requires you to program the time before using it! My Time Warner cable box will not work for as much as 15 min after being plugged in, it has to receive an updated user profile from the central office as part of its security against illegal boxes.

 

[picasm]

Irons are a much requested item. In this context the iron cannot be permitted to draw over 700W or so

Travel irons use about that much power, although they would not work anywhere near as well as a steam iron and are probably not designed to last long in everyday use.

 

[mvs sarma]

Hi Morgan,

Oznog has a real point . many appliances ( remote controlled including PC and associated CRTmonitor)drain power even when OFF. i saw articles from a manufacturer of power contoller chips, (Power Integration Inc) that very low power standby is legally insisted and they were trying to meet this end. Afterall any supplier of equipment to these zones , can be insisted for this as a specification. it will ofcourse have a long term effect. for allready working utilities, you could recommend form a committee, to suugest add on modifications to conserve this wastage, so far not much noticed. we are also in symultaneous touch with post at 181834.

 

[morg]

Thanks guys ... on your last point mvs sarma you are exaclty right -commitees are well established in every village and regularly meet to discuss all issues - power consumption, technical faults to tariff collection. It is to them I will present my recommendations.

The standby power issue I have read about ... and I'll recommend it but I'm not sure how relevant it is here. With only 200 - 300W continuous power per household most people really only have lights, a TV, radio and maybe 'daytime' appliances like a sewing machine, kettle, iron etc. dependent on their income.

I have seen plug-in Power Factor Correction devices like - **broken link removed** - am I right in thinking these things just use capacitors to align phases and draw less 'apparent power' (VA) by reducing reactive power ? If so, given that there are so few appliances in use in my case (the inductance of 5 CFL lights and a TV only real factors) would these devices make much difference ?

By the way, do household meters charge for apparent power as opposed to true power ?

 

[Hero999]

It might depend on where you live, here in the UK the power meters charge for real power but you might want to consider buying some that charge for VA so you can charge more.