Got a local used wind turbine (400w) I'm thinking of maybe picking up for cheap. We get 4-5 power outages a year where I live and it's fairly consistently windy at my house. Some outages last awhile. I average around 15kw/day electric.. mostly at night. I want 2-3days of battery backup power. Cheapest way to do this? Total off the grid noob so go easy on me. :wink:
Cheapest backup power for house? Discuss.
- Thread starter pwbset
- Start date
TylerDurden
100 GW
I vote for natural gas or diesel generator. Batteries are nice, but 15kWh/day seems like a lot to ask of batts.
I too thought of this briefly.
15kw is a lot. Maybe it's better to look at the things you'll need, fridge, computer, internet connection, lights, etc... and see what the minimum you'll need to power these things. It would actually be a nice excuse to the spouse to upgrade, "oh honey, i need that new energy efficient laptop in case we have an outage." Maybe she'll buy it, maybe she wont.
The big thing is the fridge. There are hyper energy efficent freezers out there (they're expensive though) that are designed to run on off-grid solar power systems. I think it would be possible to run off a few hundred amp hours of batteries (about the same that would be in an electric car) for a few days.
I figure you would need:
1. netbook with atom chip
2. cell phone connection to internet
3. super efficient freezer
4. lots of battery powered led lights
food and water is optional.
15kw is a lot. Maybe it's better to look at the things you'll need, fridge, computer, internet connection, lights, etc... and see what the minimum you'll need to power these things. It would actually be a nice excuse to the spouse to upgrade, "oh honey, i need that new energy efficient laptop in case we have an outage." Maybe she'll buy it, maybe she wont.
The big thing is the fridge. There are hyper energy efficent freezers out there (they're expensive though) that are designed to run on off-grid solar power systems. I think it would be possible to run off a few hundred amp hours of batteries (about the same that would be in an electric car) for a few days.
I figure you would need:
1. netbook with atom chip
2. cell phone connection to internet
3. super efficient freezer
4. lots of battery powered led lights
food and water is optional.
jondoh said:
Yikes... and here I thought I was doing so well with only 15kw/day for a 1,600sq/ft house with 2 people and 2 cats (damn those cats! I bet it's their fault! They are probably playing XBox 360 all day long!).
Every bulb in the house is CFL for example. I turn off lights after leaving each room etc. etc. I do leave two computers on all day for work reasons and the fridge is a bit old, but... ugh... time for an energy audit I guess.
Thanks for the responses so far.
TylerDurden
100 GW
I don't think it's a lot for residential usage, 3 days seems a lot for a battery bank. A 50KW bank might cost >$10K.
You could get a pretty good genset & lots of fuel for that dough... longer runtimes and service life... fewer holes in your jeans. :lol:
You could get a pretty good genset & lots of fuel for that dough... longer runtimes and service life... fewer holes in your jeans. :lol:
docnjoj
1 GW
Anyways if the power goes out in the winter, move the fridge outside! Protects the food from the bears! Former Vermonter talking. Throw another tree on the fire for heat.
otherDoc
otherDoc
dak664
1 kW
- Joined
- Aug 17, 2008
- Messages
- 317
For cheap but reliable you can't beat a used computer UPS. Many are thrown away when the SLA batteries fail and the owner discovers what the replacement batteries will cost. Connect it to flooded cell golf cart batteries in series to match the UPS DC voltage. The built-in charger will work if you have grid power to waste, else charge the batteries with PV or wind.
During an outage, run an extension cord to plugstrips in the house (mine is 100' long) and use sparingly - a few lamps, laptop, plug in the refrigerator twice a day, etc. If the batts go low you will have to wait for a recharge. Golf cart batteries store around 1KWH each, so figure from there. If you rely on a 220 volt well pump you probably should get a cheap gas generator. It will last a long time if only run a few hours a year.
During an outage, run an extension cord to plugstrips in the house (mine is 100' long) and use sparingly - a few lamps, laptop, plug in the refrigerator twice a day, etc. If the batts go low you will have to wait for a recharge. Golf cart batteries store around 1KWH each, so figure from there. If you rely on a 220 volt well pump you probably should get a cheap gas generator. It will last a long time if only run a few hours a year.
PaulM
100 W
I would agree with TD, for strictly backup use, a small generator would be your best bet. If you do go that route, make sure you use it regularly (at least once a month) so it will work when you need it. I work in the generator industry and non-use is one of the biggest problem causes.
If you want to stick with the renewable side of things, you may want to look into a grid-tie system, ie feeding excess power into the grid. This will bring at least a little return on investment, although it will have a higher initial cost. A good reference for this stuff is http://www.homepower.com
If you want to stick with the renewable side of things, you may want to look into a grid-tie system, ie feeding excess power into the grid. This will bring at least a little return on investment, although it will have a higher initial cost. A good reference for this stuff is http://www.homepower.com
deardancer3
10 kW
That old fridge may be robbing you blind.
Pick up a P3 AC watt hour meter to check out power use.
many here have done that, and the P3 saves you mucho energy money.
also available at many Harbor freight stores.
http://www.homepower.com/article/?file=HP90_pg116_ThingsThatWork&pdf=1
d
Pick up a P3 AC watt hour meter to check out power use.
many here have done that, and the P3 saves you mucho energy money.
also available at many Harbor freight stores.
http://www.homepower.com/article/?file=HP90_pg116_ThingsThatWork&pdf=1
d
Link
1 MW
15kWh/day is like average, isn't it? Most of that probably comes from heating and the fridge, though. I'd go with the general opinion and pick a generator if it's just backup. A 50kWh battery bank isn't really economical if it's just for a few days of emergency power per year.
Speaking of average, our electricity bill is apparently tiered and last month's usage went up a notch, so we got charged more per kWh. Or something, I don't know. Either way, I'm getting blamed for it. Grandma called to see what what that was all about and asked if a Wii used a lot of power. The stupid person she was talking to said "Yes", while the Wii actually uses a piddly 34W at peak. Now I have to pay for part of the bill if it happens again. :x Think I'll just keep turning off that new 20kbtu air conditioner if it looks likely to go over whatever that limit is.
</OTrant>
Speaking of average, our electricity bill is apparently tiered and last month's usage went up a notch, so we got charged more per kWh. Or something, I don't know. Either way, I'm getting blamed for it. Grandma called to see what what that was all about and asked if a Wii used a lot of power. The stupid person she was talking to said "Yes", while the Wii actually uses a piddly 34W at peak. Now I have to pay for part of the bill if it happens again. :x Think I'll just keep turning off that new 20kbtu air conditioner if it looks likely to go over whatever that limit is.
</OTrant>
TylerDurden
100 GW
Mebbee you could create an eco Wii game: "Human Dynamo"... pedal-power competitions that backfeed the grid.Link said:
MitchJi
10 MW
TylerDurden said:
Hi,
I'd vote for charging your ebike for free someplace (does the local utility have a building nearby with an outdoor plug
) and using the pack to backfeed the grid.
paultrafalgar
10 kW
+1 on genset rather than batteries. 45Kwatt/hours of storage is impractical. Just a small point on grid-tie. I have no idea whether you're less daft in North America, but my sister has a water-turbine chucking out about 2.5 Kwatts 247. It's grid-tied to avoid batteries BUT THE UTILITY INSISTS THAT HER POWER MUST BE CUT IF THERE IS AN OUTAGE! (So that the line man doesn't get electrocuted). Have you ever heard of anything so daft! Why they won't allow auto-isolation I don't know. Anyway, it's worth checking before you grid-tie.
mcstar
100 W
paultrafalgar said:
The electrocution issue is real, but with a auto-disconnect you could get around it if the lineman is prevented from touching your system. The other issue though is that once power returns your genset/turbine will be out of phase with the mains. You'll have to cut power completely to prevent a huge power spike (burned wires, damaged genset etc) and then bring the genset back into phase with the mains before connecting the two systems. There are meters designed to show the phase/speed differential between two systems. You'll need a precise manual speed control mechanism to match up the speed and phase of the genset to the mains and then connect them at the right moment when they are in synch. From then on your genset is kept in phase with the mains automatically. In affect it becomes a load when it's not producing enough power, and a generator when it's carrying some of the load.
Cheapest backup would be moving somewhere the electric service doesn't suck. Hydro Québec had a continuity index of 0.54 in 2006 and 0.49 in 2007, well within the <0.6 per year target. At this rate you'd have to live here ~144 years to accumulate ~3 days worth of downtime.
Also ~97% of that electricity comes from hydro, the first 30kWh per day costs 5.4¢/kWh and additional energy used is 7,33 ¢/kWh. (Cue haters bitching about evilness of socialist state-run utilities.)
Also ~97% of that electricity comes from hydro, the first 30kWh per day costs 5.4¢/kWh and additional energy used is 7,33 ¢/kWh. (Cue haters bitching about evilness of socialist state-run utilities.)
Power where I live is also 90%+ hydro from a local dam and the rest is a mix of Dakota wind farm and Washington state "bad stuff". It's $0.057/kwh all the time so it's cheap. It only goes down in severe weather, which is usually wind knocking down a line or heavy snows. Genset does seem the way to go for cost, but I'm trying hard to get away from oil/gas... even if it it getting cheap again.
I'm not a doom and gloomer, but I'm also, in the back of my mind anyway, trying to be bettered prepared in case the unthinkable happens and the utilities go bankrupt... or something along those lines. You never know.
I'm not a doom and gloomer, but I'm also, in the back of my mind anyway, trying to be bettered prepared in case the unthinkable happens and the utilities go bankrupt... or something along those lines. You never know.
marty
1 MW
When power goes out where I live, people start running around trying to figure out why the generator won't start? We all forget that we have gasoline powered cars and trucks. They full of gas and they start. I got big 1800 watt inverter. Hook it to my truck battery with 00 gauge wire. Truck will idle for very long time on a tank of gas. Waste of gas? Yes but it works.
dogman dan
1 PW
No reason not to get the wind turbine, other than money. but grid tie it, and use a cheap, under $400 generator to back up the house power in an emergency. An inexpensive chinese made 3500 works great for this, powering the fridge no matter how old, and a select few things like the furnace fan, and the tv. You have looked at the wind energy maps I assume, that tell you if it would be worthwhile or not? Where I live it seems plenty windy, but not enough days in the year are that windy, just the spring. 400 watts may take forever to pay for itself, but its good for the enviroment, like the ebike.
deronmoped
10 kW
- Joined
- Oct 6, 2008
- Messages
- 706
Buy a RV.
You could pick up a older one for a few grand, use the generator in it. Plus you can go camping in comfort
Deron.
You could pick up a older one for a few grand, use the generator in it. Plus you can go camping in comfort
Deron.
deronmoped said:
Two years ago I had a very mint 1989 VW Westfalia that I loved and traveled with. Then a house opportunity came along.. Westy... house.. Westy.. house.. seemed like a no brainer at the time, but now I kinda wish I hadn't sold the Westy the way the economy has tanked. I did drive the snot out of it for three years and sold it for $500 more than I bought it for so I can't complain.
Kurt
10 kW
Climate plays a big roll in energy consumption.I don't need any heating as I in a subtropical climate so usually tip in at around 6kwh a day.
If its just for a couple of power outages a year it can be good for you to stop for a while a get back to basics. Makes you appreciate your energy supply when its over.
What I have for the odd power outage is a small power pack its got 2* 18ah 12v sla battery's in it .On the front panel is a double power point and a 600w inverter built inside it also had a couple of USB jacks a large LED light and some 12v sockets.
the longest power outage we had was about 24hrs but it worked well to provide light in one room and power to my laptop and run a couple of 240v apliances from the inverter.Perishable food went into my 40lt car fridge freezer that has its own battery in the trunk of my car.I get about 2 days from that.
Kurt.
If its just for a couple of power outages a year it can be good for you to stop for a while a get back to basics. Makes you appreciate your energy supply when its over.
What I have for the odd power outage is a small power pack its got 2* 18ah 12v sla battery's in it .On the front panel is a double power point and a 600w inverter built inside it also had a couple of USB jacks a large LED light and some 12v sockets.
the longest power outage we had was about 24hrs but it worked well to provide light in one room and power to my laptop and run a couple of 240v apliances from the inverter.Perishable food went into my 40lt car fridge freezer that has its own battery in the trunk of my car.I get about 2 days from that.
Kurt.
dogman dan
1 PW
I get a lot of outages where I live. Its a long strip of city along the highway on the edge of town, so the "grid" is one power line. Summer lighting strikes take it out all the time for a few hours. Once in a while the poles get hit by a truck or car since they are 3 feet from the highway, and then we get at least 12 hours without power. When that happens I just start up my 3500 watt gennie and keep tv, computer and AC functioning. If shit really hits the fan, I'll run out of gas though. But for the regularly scheduled outages I get the $250 gennie works great. The DC output can start a car. The battery powered inverter- car starter type setups look real cool too. I'm real tempted to make one out of all the barely used 12 ah sla's I have.
TylerDurden
100 GW
If you want to stay more on the green-side, you can run a diesel genset on b100. Even greener is to convert it to also run on veggie-oil.
FWIW, grid-tied PV & wind systems automatically disconnect from the mains when the grid goes down and reconnect when the grid is restored. Backup gennies use transfer switches that fully disconnect and do not backfeed the grid.
http://apps1.eere.energy.gov/consumer/your_home/electricity/index.cfm/mytopic=10520
FWIW, grid-tied PV & wind systems automatically disconnect from the mains when the grid goes down and reconnect when the grid is restored. Backup gennies use transfer switches that fully disconnect and do not backfeed the grid.
http://apps1.eere.energy.gov/consumer/your_home/electricity/index.cfm/mytopic=10520
TylerDurden said:
Doh! Should have thought of that. Great idea. Now that I think about it there is even a local kid here who started a biodiesel company a couple years ago with fuel made out of camelina seeds grown locally. He even built his own little gas station (if you can call one pump with a plywood shed behind it a station). Think I'll look into diesel gens. Thanks TD.
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