"Hyper-Watters?" :Zero Energy Homes
 

Newsweek article on Zero Energy Homes. The utility bills are not always zero, but it's still considerably less than the neighbors....

Re: "Hyper-Watters?" :Zero Energy Homes
 

The ROI for solar panels isn't bad at all. It's about as practical of an 'investment' that can be made there days. In the last 6 months, the ebay price per watt of 25-watt panels has gone from the low $3s to the mid $4s.

Some interesting links:
http://www.otherpower.com/
http://www.homepower.com/
http://www.backwoodssolar.com/
http://www.oasismontana.com/PV_index.html

Re: "Hyper-Watters?" :Zero Energy Homes
 

I used to chuckle at the lengths the hypermilers would go to squeeze out another mpg, but realized how bad I was about squeezing out every last bit of unneeded kilowatt usage to match my solar panel output. Drove my family nuts. Following them to turn off lights. Inventorying the draw of every electrical device in the house. Putting the computer and cable modem on a switch to cut power at night. Flourescents everywhere. LED Christmas lights. Kids off to college...

Re: "Hyper-Watters?" :Zero Energy Homes
 

I've read of these before, some as far as i understand actually generate revenue for the owners selling power to the power companies

Re: "Hyper-Watters?" :Zero Energy Homes
 

My neighbor laughed when I went for R19 walls, R45 attic, and SEER12 heatpump when the houses were being built in 1998 (standard in MD was R11, R30, SEER10). He laughed when I siliconed the ductwork and outside wall penetrations, then encased the ducts in R2 foam, blanketed the water heater and put in the programmable tstat ($$$ for a heatpump variant). He almost fell over when I put in fluorescents for the lights that are on a lot.

I laugh every month when he yells at his family about the $150 electric bill. My bill is $90/mo over a year. (avg 40KWh/day over a year; 30KWh for non-heat/cooling)

Same houses (2000sqft colonial w/ walkup finished basement), same # of kids (2), same ages (elementary school).

As the kids get older, each little thing I've done has so far offset the increased usage inherent with a growing family. I'm out of easy options...next step is geothermal heat pump & hot water and then solar electric w/ a big sunroom for passive climate control.

Electric is only ~4.5 cents/KWh here, hard to recoup a $20K solar investment in MD unless you go hardcore.

Re: "Hyper-Watters?" :Zero Energy Homes
 

I find it a bit strange, how we are happy to throw $20k+ down on a new car (or 2 or 3 cars) that gets no return, yet a $20k solar setup is only considered worthy if it's going to outperform coal or natural gas. I know it's a perfectly normal reaction to spending that kind of money, but people throw that kind of money away on cars all the time. Hopefully soon we'll start to realize that the "cheap" sources of energy have expensive hidden costs.

Re: "Hyper-Watters?" :Zero Energy Homes
 

Somehow the math doesn't work out. 40 KWH x 30 = 1200 KWh per month times 4.5 cents equals 54.00 per month.

Building a net zero energy home is not that easy. Mine is capable if the numbers on solar power made sense. I have over 1000 square feet of south facing roof. I am in a southern climate with 5.5 hours of average daily usable sunlight. My 4200 sq ft home used 12000 KWH in the last 12 months. Peak usage was 1345 KWH in July. This would work out to a net zero energy home if I was willing to invest the 45k dollars for a system but the financed and amortized cost of the energy would be over 30 cents per KWh. I currently pay 8.5 cents per KWh. I'm hoping to see nanotechnology manufacturing drastically reduce the price in the next eight years. Panels for the house and more panels for the fully electric car that I yearn for.

Re: "Hyper-Watters?" :Zero Energy Homes
 

I think part of the thinking is that you need to get a car every now and then, so that~$20k cost is there no matter what- the hybrid premium is marginal on top of that, whereas adding solar is definitely a discretionary expenditure for most of us. I HAD to get another car, it might as well be efficient. I do not NEED to get another power source for my house...yet.

...call my initial hesitance 'social conditioning'? I still will do the solar thing at some point. I bought my hybrid not for the savings, but to promote technology that makes sense and in the long run can only help. Same for solar, geothermal, whathaveya.

WRT the math: 4.5 cents is the generation cost, excluding transmission. I should have added that in, which adds 2.5 cents more. Throw in a few 'fixed' fees on top of that. MD is beginning the transition to a comeptitive power market and BGE maintains all transmission, so that is broken out as a separate cost.

Re: "Hyper-Watters?" :Zero Energy Homes
 

NJ pretty much paid for my grid tied 7.5 KWatt PV system.

2 months in the spring with $2 electric bills!

In the middle of this repressive summer with the room AC's on, we maxed out at $35 / month. That includes an electric range/oven as well (oil and wood heat in the winter - I get all my wood for free too).

I'm certainly not getting all the latest energy saving devices (some of our appliances are probably 25 years old), but I'll certianly get high efficiency ones when the timecomes.

Anyone in NJ or CA should JUMP on the state sponsored programs!

Re: "Hyper-Watters?" :Zero Energy Homes
 

Never thought about it in that way! Good Idea and thanks.Kevin

Re: "Hyper-Watters?" :Zero Energy Homes
 

Josh,
Wow, a system that size must run $50K+. And they covered most of it? What is NJ's rebate program structure?

For a while here in the Los Angeles area, if you were supplied by the municipal power system, they were offering rebates up to 85% (not anymore). I'm under Edison rather than the muni system, so I only got 50%.

Mike

Re: "Hyper-Watters?" :Zero Energy Homes
 

Here are the program details: http://www.njcep.com/html/2_incent.html

System was something like $50k . . . we spent less than 10. I forgot to mention that I also have full battery backup for 6 important circuits in my house (computers, fridge, WAP, etc...). That portion was NOT covered in the program - out of pocket, but it was obviously installed at the same time.

How does one add a picture? I'll post those too . . . the pv's, grid tie, invertors, charge control units, deep cycle batteries . . . more complicated than I orignally thought it would be!

Re: "Hyper-Watters?" :Zero Energy Homes
 

I think I've figured it out . . .


https://www.greenhybrid.com/share/image433.html
https://www.greenhybrid.com/share/fi...-Batteries.jpg
https://www.greenhybrid.com/share/image432.html
https://www.greenhybrid.com/share/fi...6/Solar-PV.jpg
https://www.greenhybrid.com/share/image431.html
https://www.greenhybrid.com/share/fi...leBasement.jpg

Re: "Hyper-Watters?" :Zero Energy Homes
 

Thanks for the link.

I discovered (too late) that the cost is not linear to the amount of kW capacity. My 2.5 kW system retailed for $25k ($10k per kW), and a neighbor's 5.0 kW for $36k ($7.2k per kW). He used the same vendor and equipment as I. The per-kW rebate doesn't distinguish how much you paid per kW, so he had a higher percentage of the cost rebated. I wish I had added another kW or so at the time. To do it now would cost $7.5k to save the remaining $75 per year I pay for electricity (100-year payback, no thanks).

Mike

Re: "Hyper-Watters?" :Zero Energy Homes
 

This is the thread that inspired me to start tracking my electricty usage on a day to day basis rather than just once a month via my electric bill. This is also around when I was converting all lighting in my house to CFL's, when my roommate moved out, and when I decided to experiment with just how far I was willing to go in terms of allowable temperature fluctuation to reduce energy consumption.

I've attached a spreadsheet I've been using to track my power usage since I purchased my home way back in early 2000. You can see bar graphs for total usage per year, the individual consumption for each month, and for the last two months or so, you can see where I've been tracking it daily. Part of my motivation for this was when I realized that I spend more on electricity than I do on gasoline every month, and that since I'm already driving about as efficiently as possible, the next logical step in saving money was to reduce electrical consumption.

You can see for the last two or three months, I've been near or better than ever in the history of my home ownership in terms of reduced power usage. For the last couple weeks, I haven't used heat or A/C at all, and virtually all the power usage has been just from the water heater, washer/dryer, fridge, and to a small extent, lighting and computer usage. To have a significant impact now, I think I'd have to buy one of those instant-heat variety water heaters that only heats water when you're actually using it, and has no "tank" to speak of. That might save me 2-3 kw/h a day.

Re: "Hyper-Watters?" :Zero Energy Homes
 

Nice job with the reductions. Going after every kWh is addicting, isn't it? ;)

We got our highest savings with: CF lighting, turning off exterior ornamental lighting, setting computers to hibernate, turning off cable modems and wireless hubs overnight, and killing power to all those devices that use those square transformer plugs. The plugs can draw 10-20 watts, even with the device off. You'd be amazed how much those nickel and dime items add up when burning 24/7.

FYI, attached is our monthly and average daily kWh usage for a 2300 sq. ft. house over the past few years. Note the large drop in 2003 when we decided to get serious. Climate is everything - we don't need AC.

Mike

Re: "Hyper-Watters?" :Zero Energy Homes
 

Efficiency gains are definitely addictive. Once I purchased a pair of CFL's I couldn't quit until I'd replaced nearly every single light. I used my Kill-A-Watt to benchmark pretty much everything in the house that has a plug, too, in search of areas to improve. The only big unknown at this point is the water heater, but like I said, since I've had two days where I wasn't home and thus only the fridge and water heater were drawing power, I almost know what the water heater uses just to idle itself, but still I wish I could put a power meter on the water heater itself to know for sure.

I'm incredibly impressed with your low usage. Hardly any months month over 15kw/h per day since 2003, and it looks like an average of about 12.5kw/h per day. I assume you have some sort of non-electric heat then? My home has a heat pump, so both the heating and cooling are electric. As mentioned, my water heater's electric too. Basically it's an all-electric house; nothing solar, no natural gas. I might experiment with space heaters this winter to save a little on heat and maybe get low-E window treatment for my glass before next summer. Based on my usage now versus my usage in July, it looks like 75% of my July bill was A/C. Too bad it's so dang expensive for the very high SEER rated heatpumps. Payback on a $9000 unit is longer than how long it would probably last in the first place.

Re: "Hyper-Watters?" :Zero Energy Homes
 

About the tankless heaters- I've thought about them, but I'm not sure they save for a family-size household- capacity is simply not there for 5gpm @120deg for electric models. They claim it, but I've had 3 installers tell me it just ain't there. For small households they should work great.

Have you put the heater on a timer? shut it off except for a few hours before you use hot water, and wrap the heater in another layer of insulation.

My ideal would be a tankless instant heater at each point of use. Only one run of piping through the house- fewer points of pipe failure, and if one heater goes you still have hot water at the other spots.

As for the quiescent transformer loads- I'd love to install a DC voltage bus through the house, supplying 12V regulated down locally or multiple busses (nightmare wallplate!). A single mongo power supply is more efficient than many small ones, and something is almost always drawing a load, so the quiescent power isn't like an idling engine- there is always a real load somewhere. Modern houses have enough DC power demands to make that an interesting build option, although many items that have the brick internally (PCs, DVD, etc) and would require some wiring mods. This dosn't solve the clock-in-the-microwave problem, though- those phantom loads will remain.

Even better would be switching power supplies instead of bricks. <<1W drawn at idle, but lots of RF noise (like in CFLs). I think only 1 place has them commercially available, and they are very pricey.

Re: "Hyper-Watters?" :Zero Energy Homes
 

We're all natural gas for heating, cooking, etc.

Re: "Hyper-Watters?" :Zero Energy Homes
 

I have on-demand hot water, but its fired through the oil burner, which sort of sucks.

Electric is down to less than $1 per day.
Gasoline is tracking at $2.21 per day (for my commuting car, not other vehicles).

HOME HEATING OIL is the bill I have to work on reducing now!

I've got a couple cords of wood for this winter, but getting the heat through the rest of the house is by far the biggest challenge, and there is no easy answer for my hot water issues.

good thread all!

Re: "Hyper-Watters?" :Zero Energy Homes
 

Wow- old school.

Growing up we had that, then put in solar hot water with the oil burner as backup/supplement. This was in NY.

Re: "Hyper-Watters?" :Zero Energy Homes
 

[QUOTE=gonavy]About the tankless heaters- I've thought about them, but I'm not sure they save for a family-size household- capacity is simply not there for 5gpm @120deg for electric models. They claim it, but I've had 3 installers tell me it just ain't there. For small households they should work great.

Have you put the heater on a timer? shut it off except for a few hours before you use hot water, and wrap the heater in another layer of insulation.

My ideal would be a tankless instant heater at each point of use. Only one run of piping through the house- fewer points of pipe failure, and if one heater goes you still have hot water at the other spots.

QUOTE]

I have a brother-inlaw with a tankless waterheater and he seems to like it but I've also seen him having to run the water in the kitchen for about a min just to get hot water to it. Wonder how much it costs him in the wasted water. Point of use water heaters sound like that would take care of the wasted water but then there is the extra cost of having 3 extra water heaters.Kevin

Re: "Hyper-Watters?" :Zero Energy Homes
 

Ok, for those of us who live with slightly lower demands, even electric tankless can work just fine. Check out this spec page:

Tankless water heaters

The "cold" water in Phoenix never gets below 55 degrees or so, and I like about a 95 degree water temp for washing up. I have a 2.1gpm @ 80psi shower head, although actual water pressure is 65-70psi, so figure it only really flows maybe 1.8gpm. The smallest model listed on that page can do 1.5gpm with a 41F rise, which would almost meet my needs. The next one up Says it will do 63F at 1.5 and 48F at 2.0gpm.

If you then skip up to the top model, it's rated for 75F at 2.0gpm, which means if you only wanted a 40F rise, you'd be mixing in enough cold water to get a total flow of 3.5gpm or so. That should just be sufficient for two simultaneous showers on the same hot water feed.

The other alternative would be gas fired ones or even multiple units. One of my co-workers has a large house, so one end of the house with the kids rooms and kitchen stuff is on a large water heater loop. The other end of the house with the master bedroom and one guest room has a separate hot water loop with a tankless heater. I personally would kind of like to have one since I hardly use any hot water at all (maybe 20 gallons a day?) but the 50-gallon, dual element water heater of mine sits there all day long heater water to 120 degrees. It also takes up a bunch of room in my small garage.

It's not really something I'm looking to do right away but I think at some point I'd like to try a tankless water heater. Someone also asked if I've gotten a water heater timer. I have not, but I've experimented with using the circuit breaker to manually turn the water heater on and off. There was almost no benefit to only running the water heater in the morning, and there is certainly a downside to having no hot water at night if I wanted to take a shower. That's really where a tankless water heater would be the best use of energy. They also make real small ones you can put under sinks so you have instant hot water at your sink too. That helps you to save water as well as power.

Re: "Hyper-Watters?" :Zero Energy Homes
 

Having your water heater far away from the kitchen would be the same regardless of if you had a tank or tankless water heater. There's two ways to solve that; point of use water heaters (like you mentioned) or a hot water circulation loop. The circulating loop is great for saving water, but it requires power to constantly heat all that circulating water since heat is constantly lost in all the piping. Even with a solar heater included in the loop, that would only offset the water heating for a portion of the day. It then becomes a question of which do you want to conserve more: water or power? A point of use tankless water heater would let you save both, although at an increased up-front cost since you'd be installing water heaters at every major point of use.

I guess the ultimate would be a hybrid where you have a hot water loop with a fully solar heater tank that is set either unregulated or set to achieve some potentially very high temperature like 140 or 160 degrees or whatever peak temp you can reach via solar. Then have the solar heated loop feed all the hot water lines. Sure, it would lose heat through the pipes as it circulates, but even overnight it could probably maintain a water temp well above the standard cold water, thus saving power for the on-demand heaters to only achieve a much lower temperature rise. Come to think of it, hybrid makes everything better, doesn't it?

Re: "Hyper-Watters?" :Zero Energy Homes
 

You could also use a plate heat exchanger off the high side of a heat pump,run water thru it and into the waterheater and back, waterheater would then be used only for back up or when heat pump isn't running. I've seen this work and it saves quite abit of energy. Kevin

Re: "Hyper-Watters?" :Zero Energy Homes
 

Most geothermal heat pumps use this desuperheater technique to provide free hot H20 from the heat rejection in cooling mode, and can also (pre)heat in heating mode, at cost.

To qualify for the new $300 Federal credit, a geo system MUST have a desuperheater! Why heat up the Earth's crust when you can heat your water instead?

from the energy bill:
Sec. 1333 Credit for certain non-business energy property (page 1351)
One of the highlights of the new bill addresses homeowners, who are granted up to $300 in tax credits for the cost of new Geoexchange systems. To be eligible, the standards that must be met are 14.1 EER & 3.3 COP for closed loop, 16.2 EER and 3.6 COP for open loop and 15 EER and 3.5 COP for DX. However, the system must include a desuperheater or integrated water heating to meet the credit's criteria.

http://www.geoexchange.org/incentives/incentives.htm

An air-air heat pump can do it too- still free hot H20 in the summer, at least. Almost certainly not worth the cost in winter, though.

Re: "Hyper-Watters?" :Zero Energy Homes
 

This is an excellent thread. :lightbulb It shows that guys/gals posting here are concerned with the environment.That we also get some wallet benefit, it is only the icing in the cake.

Re: "Hyper-Watters?" :Zero Energy Homes
 

Actually, I was thinking I might ask Jason if he could set up a new forum when he is between semesters. One for 'home hyperwatting' or something along that line, so we don't have to squat in the catch-all forum..

Its OT from the point of this site, but very closely related in the larger picture. And many of the same hypermiler philosophies play out similarly in a house too.

Re: "Hyper-Watters?" :Zero Energy Homes
 

Ok, so kind of on the subject of energy conservation, I have had my refridgerator plugged in to my Kill-A-Watt for a few days now. I also have a thermometer in the middle of the freezer to monitor temps. I noticed it's doing a defrost cycle right now. Does anyone know how often the average fridge does this? Like once every 12 hours, 24 hours, 3 days, etc? It was drawing a good 600 watts to provide the initial heat to get the defrost cycle started, and then appears that it shuts off and just lets the freezer warm up naturally for a while before it goes back into cooling mode.

So far, the total kw/h consumed seems in line with readings from my previous data recording session (which spanned about 60 hours) but obviously a defrost event would affect the numbers, so like if one experiement had 2 defrost events and the next experiment only had one, I don't think they can be fairly directly compared.

Oh, and for the curious, I previously had the freezer set at "5" out of 10, with 1 being warmest and 10 being coldest and the fridge is set at "6". The 60-hour average with those settings worked out to about 2.18kw/h per day. I'm now 24 hours into having the freezer set to "1", which outside of the defrost cycle appears to have raised the average temp from about -2 to about +7 and it's used 1.90 kw/h in 24 hours.

Re: "Hyper-Watters?" :Zero Energy Homes
 

AFIK defrost happens every 24h on a typical fridge/freezer combo.