Electric Water Heater

Page 1 of 2  
How are newer electric water heaters more efficient than old ones if they are in a heated living space.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

summer (when it is a cooled living space)
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
ROANIN wrote:

mass inside the isolation area. Also stopping in time when the temperature is where you want it. And then beep for attention.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Sjouke Burry wrote:

So if I have an electric heater that is an old Westinghouse that I figure was made in 1954 or so, would I save money with a new model? I figure that any heat lost out of the water heater would be offset the heat required by my furnace.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
ROANIN wrote:

So (almost) all people have natural gas heating. Loosing heat from electricity is not compensated on de heating of our house. If you heat with electrcity, then yes, there is no net loss.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Fri, 03 Dec 2010 08:02:49 +0100, Sjouke Burry wrote:

Correct - but to be a little more accurate, if you heat with electricity fed using the same supply as the (electric) water heater there is no net loss during the heating season. We have about 14kW of electric baseboard under load control at something like 4.5c/kWH, with the water heater on the regular supply at about 8.5c/kWH, so despite the electric heating there is a benefit to making the water heater as efficient as possible.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Fri, 3 Dec 2010 13:52:53 +0000 (UTC), Jules Richardson

you cut the amount of gas the water heater uses by 15%, saving 15% on the power used by the water heater to maintain water temperature - of which half is reducing your heat supply power, for a net saving of roughly 7% of the power your water heater uses to maintain temperature - which is alrady a small fraction of the power your water heater uses. If it was possible to save 2 or 3% of your water heater overall power consumption I'd be VERY surprized.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Here in New England, electricity is about 17¢ on average.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

One of the (many) reasons I moved out of NE.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Fri, 03 Dec 2010 08:02:49 +0100, Sjouke Burry

This and several other replies assume that "heat with electricity" means electric resistance heating.
A heat pump (which is also electric) is more than 100% efficient, in the sense that the thermal energy delivered to the interior is greater than the electrical energy used to pump the heat. This applies to an interior temperature of about 70F and exterior temperature down to about 15F. With a greater temperature difference (exterior below 15F) the heat pump efficiency drops below 100% and you are better off switching to resistance -- as some heat pumps do automatically.
Edward
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

In that sense, everything is 100% efficient, because mass-energy is always conserved.
This viewpoint however is not particularly useful to someone trying to figure out how to heat a house.
For a discussion of efficiency to be meaningful, you have to say what you are measuring with respect to. Absolutes are not useful.
Edward
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

No it is not. It's an agreed upon measurement of inputs and desired outputs. Just stating your number is not scientific at all.

Then why did you state that electric water heaters are 100% efficient?

Which you've demonstrated is beyond your grasp.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Dec 5, 12:45pm, " snipped-for-privacy@att.bizzzzzzzzzzzz"

electric water heaters are 100% efficent, except for their tiny standby losses.
Too bad a BTU of electric heat isnt as chaep as a BTU of gas heat, electricity to heat costs a fortune:(
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Those "tiny standby losses" are a function of the amount of water used, so your statement is nonsense.

That's certainly dependent on location and why heat pumps are common.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Thttp://en.wikipedia.org/wiki/Electric_heating#Environmental_and_efficiency_aspectshen why did you state that electric water heaters are 100% efficient?

You're totally clueless. Efficiency is defined as the energy in divided by the *USEFUL* energy out (not that you'd ever understand the concept of "useful"). Since water heaters lose heat to the environment they are *not* 100% efficient.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

electric tanks are heavily insulated and lose very little to stand by losses.
so 99% is that good enough for you?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

m> wrote:

no put the energy label on all new heaters gives a efficency number. which for electric is always very high
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Thttp://en.wikipedia.org/wiki/Electric_heating#Environmental_and_effic...you state that electric water heaters are 100% efficient?

It's useful as a comparison with like units. Otherwise it's less meaningful.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Thttp://en.wikipedia.org/wiki/Electric_heating#Environmental_and_effic...did you state that electric water heaters are 100% efficient?

No you can't. Eff == Eout/Ein, or in this case Eout/(Eout + Eloss). Eloss is a constant but Eout is variable with the quantity of water used, but can never equal 100% (Eloss is finite).
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Thttp://en.wikipedia.org/wiki/Electric_heating#Environmental_and_effic...you state that electric water heaters are 100% efficient?

You Brits really are stupid.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Related Threads

    HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.