Personal Best Monthly Electricity

The house faces SE and in winter, an enormous amount of sun pours in. In summer, with the roof overhang, the sun barely touches the window jambliner

The development I live, the houses are 4-6 years old. My house is one of the few with a +90% furnace, the rest are the older style with non-sealed combustion and a draft hood. Though no pilot, ignition is sparker

I know the neighbors don't heat much warmer than 72 F in winter. I have to keep things toasty at +76 F and warmer, due to having an elderly person in the house with me. Way to hot for me, I usually have to walk around in shorts and a tee, even in the middle of winter

I've been in the neighbors homes. The regular appliances (Fridge, dishwasher, clothes washer, etc) are fairly low end, all of my major appliances are Energy Star rated. I also sealed and insulated my ductwork, that made a huge difference too

With Manitoba Hydro, it would cost about the same to heat a home with an electric furnace, vs a +90% gas furnace. Electricity up here is very cheap. If you want an idea of how different heating works out here, check out this Manitoba Hydro site

http://www.hydro.mb.ca/your_home/home_heating_comparisons.pdf?WT.mc_id=2815

Power Smart for Your Home

Their estimates must be based on a smaller home. Nobody I know has heating costs as low as they state, usually 40-60% higher based on technology used (Eg, heat pump, high eff furnace, etc). However, the ratio is about correct

I should point out that I have a Reznor forced air heater in the attached garage. At my request, they had a temp meter on the heater for a month. It costs around $50 a month in cold weather, to run the garage heater

 

Thanks for the info, jayman. That sounds about right to me based on the home size, your much colder winters, the type of unit you have, and the temps you have to run.

In general, with fossil fuel based electrical generation, it doesn't make sense to me to convert electricity back into heat through resistance heating. (Heat pump is another matter, esp. geothermal.) The efficiency in generating the electricity is not high so using gas directly for heating makes more sense. Of course that really doesn't apply to hydro, nuke, or renewables... Well, I guess it still applies to PV solar as the conversion efficiency is low and the capital cost is high.

 

I'm shooting for 200 kWh/month maximum and no NG. We'll see. I'm putting down pavers today for my outside laundry line, and have to shoot off an email to the guy who is going to help me install solar heating to approve my equiptment choices. Later in the autumn I'll install my southwest facing windows.

I did receive the kill-a-watt power measuring device, and over a week measured 2 kwh/day for the refrigerator. I think I'm better off putting the money that a new one would cost into another window. Since my budget is 7 kwh/day, I still have 5 kwh left over for lights, electronics, and non-hot water related machine use. I'll actually be surprised if I have a problem staying in budget.

 

Properly installed, geothermal heat pumps are remarkably good at heating/cooling the average home. I have co-workers who live outside of Winnipeg, in rural areas. Their yearly power bill is around $650

Improperly installed, however, you have a nightmare to deal with

 

What do you see your other major loads as? How many occupants? What have you been averaging?

We cook about twice/day on average so I've allotted 2 kwh/day to the range/oven (no guage for this one.) We also use the dishwasher once/day, air dry, but the sanirinse pushes it to 1.1 kwh/day (metered.) Front loading washer once/day is 0.11 kwh.

Since you aren't planning to use the dryer that knocks out a big load (about 2.6 kwh/day for us.) But between TV and desktop PC's we've got a pretty substantial load. Lighting costs for us are low in the summer.

 

2 kwh/day is between 2 and 3 times a new energy star fridge will use. You do have to watch a Kill-a-watt on a fridge and leave it on long enough to make sure you do a proper evaluation,, a week or longer is good,, as auto-defrost will skew a number considerably in the short term.

A modern Energy Star will use .5-1kwh/day some even less.

Jay makes a great point about a ground source heat pump,, or even a waste heat into hot water medium heat pump.


Icarus

 

Do we get to chime in with our net usage after solar is taken into account? I've got you beat by a mile!

Without accounting for the EV, we do about 300 kWh/ month in our 2,250 sq ft house... before solar. After solar... zero.

I've got the same wants, really. Except I DO want to get rich.

 

Depends on the size and configuration of the fridge being replaced. Nearly all traditional family refrigerators (top, bottom, or side-by-side) on the Energystar list are over 1 kwh/day. To get them under that would require some warm settings inside and/or cool home temp.

I filtered out "refrigerator only" and freezer only types, manual defrost, as well as those that are "inactive", then eliminated anything below 16 cu.ft. total volume. That left a few that were below 365 kwh/year, precisely 3 out of 825 listed. Two were at 365 with the rest over. The median was 478 kwh/year, the mean was 498 kwh/year. None with over 19 cu. ft. came in below 403 kwh/year.

Using the median value it would be reasonable to assume that the average Energystar refrigerator would consume about 1.3 kwh/day. That is what my 25 cu.ft. French door with icemaker uses.

 

Shawn,

You have obviously done more research than I. I bring some of the numbers from my solar forum and the real world reports via kill-a-watts there.

We just put a fridge in a summer rental house that uses ~.6kwh/day. Simple Kenmore.

Tony

 

Two adults, two teenagers. I currently average about 800 kwh/month. This includes the electricity to heat the water for 4 showers a day, and 1 - 2 dryer loads.

Our main power uses after I remove water heating and drying:
Cooking (all electric through toaster oven, microwave, and stove)
Fridge as noted above
Dishwasher once a day
CFL lighting
Fans on hot days
Phantom losses -- not counted yet. I have not succeeded in coverting my family to power strip use yet. I may yet have to throw out the remote controls.
Home network 7/24: printer, router, tele adapter, modem

Low to none:
No AC
No desktop computers
TV use typically only to watch Tiger

 

Sage,

Consider simple solar pre-heat,, ideally supplemented with demand gas/propane. Depending on climate (freeze issues) you can build/buy/install a simple flat plate water heater collector fairly reasonably.

I have a simple home made collector that produces ~60-75% of our hot water on a year round basis,,150% in the summer,, perhaps 25% mid-winter, in the Pacific NW.

 

Icarus,

If you mean passive solar for water heating, absolutely. I've been lazy in getting it up and running because I have to dig a rather long ditch and make supports for an installation on a little hill next to my house, but I'll get it done soon.

 

That water heater is your biggest electrical load, probably something like 300 kwh/month. It sounds like your region is a much better match for solar water heating than ours so in looking for electrical load reduction that is probably your best bet.

In the interim the easy items to reduce hot water energy use are (in order of expense, not impact):
1. Adjusting the temp down to around 120 F if you haven't already. It is free.
2. Applying some pipe insulation to any exposed hot water lines. Don't forget to insulate the cold water line into the tank! (Doesn't apply to gas water heaters as you aren't supposed to put insulation near the vent stack.) This will reduce some of the thermosiphon effect of hot water rising in the exposed line, cooling, then falling back into the tank. Insulation is about $1-2 per 6 feet.
3. Put an insulating jacket on the tank. Even though the tank skin won't feel hot it will be several degrees above room ambient temp. Adding the jacket will cut the losses from the tank surface roughly in half. Cost is typically around $20-25.
4. Try a low flow shower head...or two...or three. By low flow I mean something in the ~1.5-1.6 gpm range rather than the standard 2.5 gpm range. The most efficient will be the non-aerated head designs because aeration causes some cooling of the water, more misting, and therefore requires the user to turn up the hot water mix to compensate. However, the aerated designs will still use less hot water than a 2.5 gpm head would. What works for you or your family is of course a very subjective thing. Some like the inexpensive Delta low flow (Tripp). Icarus likes the Oxygenics (aerated). The HighSierra worked well in my daughter's shower. I'm going to try a Roadrunner in my shower when they get the brushed nickel finish in stock. Price range for the shower heads mentioned above is roughly $10-$45 each.
5. Front loading washer--assuming you do some warm or even hot loads periodically. This won't apply to cold/cold loads. The front loader takes about 1/4th as much hot water for the same size load as our old top loader did. Front loaders start in the $600 range.

 

I'm currently in the design phase of building a new home on acerage. This time, am going geothermal. I intend to make use of passive solar, not sure about active solar due to the severe winters here

Am leaning towards a partially earth sheltered home, as the land is hilly and a few spots have a nice SE exposure. I also have to consider which site to use, as the area has trace arsenic in some test wells, depending on depth.

Very early stages, may not even get to breaking ground this year.

 

That's pretty good. Tripp reported 0.69 kwh/day in mid winter with his 18 cu. ft. Frigidaire. It is rated at 383 kwh/year based on the model #'s Energy Guide. So, yes, there is room for outperforming the Energy Star ratings by a good margin, particularly in cooler months. I just wouldn't advise anyone banking on it when considering a purchase.

Besides, you solar folks can be pretty clever about figuring ways to wring a few kwh less out of an appliance.

 

Truth be told,, I am talking about an active system, one with a pump and a controller.

Shawn,

Most climates in N. american make solar hot water pay. Even in cold climates like Jay's there are remarkable efficiencies that can be had with a glycol system running through evacuated tubes. I run a pure water system with drain back when it is really cold,, and freeze protection down to ~10f. Even in the notoriously cloudy (winter) Pacific N.W. has considerable gain even in the winter. As I suggest,, I get ~25% gain in the winter,, +150% in the summer.

You don't need warm weather for solar hot water,, just some sun. Evacuated tubes do significantly better in partial sun than do flat plate collectors.

Icarus

 

I'm not saying it won't pay, just that I'm following the mantra of conserving first, before committing to what amounts to major utility changes.

There are at least three contiguous months a year here when the average daily temp is around 30 F. I'm leery of a water filled system for those months and would have it drained at those times. Which puts me into a glycol system if I want to get anything out of those months.

25% for two people is 12.5% for four. 150% for two is 75% for four. You've already gone to a low flow showerhead and I suspect you are thriftier than most with hot water as well, :hail: so I don't expect to gain anything on you in those areas. That means I would need a larger system, perhaps twice as large.

I want to minimize consumption first, then consider what sort of thermal solar water heating system would fit on an annual basis, and considering typical usage patterns. Afterall, I need the most water heating in winter anyway, and the least in summer.

Even with amply sized solar I would still need gas water heating, and whether or not I end up with on-demand or sealed condensing w/storage tank I'm looking at a 32% water heating gas reduction for upgrading that system. (The Flamelock equipped water heater I have now is known for its unreliability so I expect it to be very short lived.)

 

Another "solution" in search of a problem. I should have stocked up on old fashioned hot water tanks when I had the chance

 

My simple flat plate collector is sized for two peoples estimated needs. (36 sq ft) If I double the area I wouldn't double the cost,, or if I used a commercial collector,,the efficiency would be much higher so the requisite percentages would also be higher. (Mine is just 1/2" copper tubing on a piece of steel under glass) A copper collector is ~75% more efficient. My collector was built at no cost however,, just scrap copper and time.

My controller has an anti-freeze setting that starts the pump flowing water through the collector when the temperature nears freezing,, running a bit of warm water through the collector. The collector temp rises,, the pump shuts off. The net/net is that the pump only has to run a minute or two an hour to keep the collector from freezing. I have used this system for years with temps ~10f with 65 mph winds,, creating an effective wind chill on the collector or -15f or so.

I also have a very simple drain down system so that if I leave for several days,, it drains completely so in the event of a prolonged power outage I don't have to worry.

As I said,, the system was pretty cheap to build and install,,, $150 for the controller, ~$150 for the pump,, everything else was scrap. If I had to buy the copper I might have spend ~$200 for the copper and a few bucks for the steel collector plate. The glass comes free from the glass shop,,, recycled patio door glass panels.

Icarus

I agree that conservation is your first, second and third order of doing anything before considering any solar option.