*
Does anyone have any observations on using solar energy and possibly propane to become grid in dependent. Right now the cost of this system is somewhat high. Does anyone have any thoughts on when or if this system will become cost effective.
Discussion Forum
Discussion Forum
Up Next
Video Shorts
Featured Story
The RealTruck AMP Research Bedsteps give you easy access to your truck-bed storage.
Featured Video
Highlights
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Replies
*
Don: I know two guys and two couples who live off the grid (and off their unemployment checks) here in Kasilof Alaska. Three Kysinski cabins and one treehouse (no s**t!). They heat with wood stoves, use propane for lights and cooking. In the winter the freezer is a fish box on the porch and in the summer they eat fresh salmon or spam. In the summer they haul water from the river and in the winter they fill their gerry cans at the Merchantile.
But back to your question, which implies that you think Edison had some good ideas and that you want electrons to remain in your life. Without getting into wind, wood stoves, I'll try to stick to solar (PV's?) and propane.
For a system to be at all automatic, you're going to use a bank of batteries (could be 12-volts - that's easy and versatile, or some higher voltage for more efficiency) and an invertor to create 115 and 230 volts. Then how to charge them? The cheapest solar panels I've seen are around $6/peak watt. A lot of those and no TV on cloudy days, you could be set. Use a propane fridge/freezer. An occassional top-off from your car alternator is the low-buck back-up.
But if you want to have power tools, home electronics, etc, your roof won't be big enough for all the PV panels you need. Then go with a propane generator to run the big, intermittent appliances and to top off the batteries during long clouds spells. They make them for RV's, job sites, and emergency stand-by power. Grainger's has some. If you are a plumber, electrician, and engineer; consider doing co-generation and recouping the heat of the generator for space heating and DHW. Post more specifics: location, high or low budget, desired lifestyle, etc.
As to future price reductions: I don't expect solar panels to get cheaper quickly. Everyone's been hoping for that for 25 years now, but it's only happening slowly. Invertors HAVE gotten cheaper, bigger capacity and more efficient once they went solid state. That should continue because the cheaper units are created more of a market. Generators have and will continue to be overpriced. If you are a cracker-jack mechanic you can cobble together some car alternators and run them off anything from a lawn-mower engine to a V-8 from a wrecked car. And convert it to propane. $200-500 of used parts. But off-the-shelf, you'll drop $2,000-8,000 on a ready-to-go propane generator. -David
*I was involved in several jobs last summer that were pretty large size homes going in off grid. One especially was a 6,000 sq. ft. log model that was going to house a family of 4. The system provided all the power I needed to run my 13 amp saw with other subs using the same source. I don't know all the specifics but it was a Photovoltaic array with a propane generator back up that ran through an inverter with a bank of storage batteries. The array was not that large, perhaps 10x20? and the bank of batteries didn't take up much room either as I remember. They planned on a full house full of appliances and were going to have 220 for a dryer also.The whole setup was going to run the guy about $15k which didn't seem unreasonable to me as he saved twice to three times that in property value. The other job was a modest 2000 sq. ft. "cabin" and the PV array was only about 6x6, 2 storage batteries and an inverter and that also ran our saws without a problem off a 100' cord. A beautiful site that if power was available would have been worth much more. This system was about $5k. I don't know about the rest of you but the idea of living without the umbilical cord of mainstream society attached doesn't seem like too bad of an idea. By the way both of the above parties were thinking of a wind generator also.
*Bob: You're right. Any roof is big enough to hold enough PV panels. The area of panels effects how LONG you can run appliances each day. As for appliance size (amp draw), one is limited only by the rating of the invertor. And limited in your run-time by your battery capacity.If those folks with plans to use a 220-volt dryer haven't committed yet, tell them to get a propane dryer. It will cost a bit more but will dry clothes in half the time and cost less than running a generator to charge batteries to power the invertor. I'm waiting for 2000 watt invertors to get cheap enough to use them as job-site power sources for skil saws, table saws, etc. Read about someone doing that (in FHB?) with a customer's invertor to power the construction of an off-the-grid house. I already use one for hand drills. It's nice to not have a generator rumbling away. -David
*Actually the PV panels were not mounted on the roof of either job but on a pole away from the house slightly. My guess is easier access for service? I questioned the electric versus propane dryer myself and the owner seemed to think the electric was a better deal?Sunelco of Hamilton, MT is the company that I have the catalog of and they sure have alot of gear!Off Grid dreaming, or Y2K reality?
*The electric dyer might be percieved as using "free" energy from the PV panels, ignoring capital costs. But with such a well-applianced house, I suspect that they'll be using that generator every day or two except in the summer.Most of our Y2K whackos up here, do not, unfortunately, have the resources to be off-the-grid unless they take the wood heat and propane light appraoach. Unfortunately, the do have the funds to be fairly well armed.
*Maybe they were considering wind generators because that would generate power in stormy conditions while the same storm clouds would block the solar array.It strikes me as rather strange that such elaborate photovoltaic technology is used to turn solar energy into DC, then AC, then run thru a dryer to heat and dry clothes that could be left outside on a clothesline. Maybe I'm a purist.
*Here in the Adirondacks there are a dozen or so folks off the grid in my neighborhood. Systems range from 5K$ to 15K$, and are often underwritten by the power company (they are forced to by the state) when it is more cost effictive than to run a line to remote homes. Propane fridges, clothes dryers, and domestic hot water are often used.Several folks have wind turbines, but they are not always that cost efficient as there is no way to store the high power they put out if there is no domestic load. (Can't charge batteries with KWs) Check out Real Goods Solar Source Book (Called Real EXPENSIVE Goods around here), or Fowler Solar Electric in MA (much better prices and equally up to date).There is an annual solar homes open house in our area, and probably more in other places.The technology and politics are changing quicky - here is New York State they just introduced 'net metering' where you are energy independent, AND on the grid. For residential customers, you can put solar etc. power back into the grid, and be paid the same price you buy power at. This is the best of both worlds in my opinion, as you dont need a huge bank of batteries, or a back up generator (the grid is your battery), and you can put all the energy you make (especially high-power sources like wind) into the grid, and use it as you need it at no added cost. A much smaller battery bank will carry you through when the grid is down, and when you are on vacation, all the power you make is money in the bank! What makes this possible is new inverters that phase lock with the grid and meet the strigent power waveform requirements that the utilities require, yet cost about 3K$.Solar panel technology is changing really fast too. New, high efficiency, amorphous silicon panels, that are less than a quarter inch thick, will cut the cost/watt by two thirds in 5-10 years, and the cost/watt will crossover that of the grid, so more folks will go this way. They are already available as a asphalt shingle replacement! (See FHB back issue for photo). Further, the deregulation of power companies (such as that in NY and CA) will support net metering and power source choice, and we will be charging our cars as well in that time frame (5-10 years).Personally I'm going to wait till the cost/watt crosses over with the grid, then make the investment.Our neighbor has a fully functional solar powered home. During the ice storm of 98, the grid was down between 5-14 days depending where you live. She was sitting in her home watching the coverage on TV when I came over sheepishly to grind some espresso beans. I return the favor when she wants to plane wood in our basement.
*Before one can make an intelligent response need to know where you are and why you want to get into Photovoltaic electricity.Having lived with PV I can tell you that it is not cost effective if you have grid electricity available. Also, it demands a change in lifestyle and thinking. You are esssentially running your own electric utility after all.So, where do you plan on putting this system? Grid power available? Do you have any plans on how to heat the structure? Refrigeration? Handling large loads like pumps, saws, etc?
*
Fred,
I will try to give you some background so you can better understand my question. I live in Tennessee on a farm and I was raised on a cattle farm. We grew up with utility elec but a private well. I would classify myself somewhat the independent sort. I am a residential contractor, and I have made a basic study of solar elec. I also understand that when it breaks I have to fix it.
After some extensive power outages in recent years I have been made even more aware that the power company has you by the b***s. Being the independent non corporate type, I don't like it.
I am planning my new home I plan on living in the next 50 years. It is 700ft from the grid. I will be building a shop building approx. 200ft from the road and plan to hook it up to the grid. I am considering using a propane fired geothermal heatpump and I would like to run my pump off of solar. I realize that I will have to buy one of those high dollar, super efficient refrigerators. I would like to stay away from mounting panels on poles. I would really be interested in a roof mounted panel or maybe those solar shingles.
I realize that connecting to the grid would be cheaper even though I would have to set a few poles to get the power to my house. I really want to put my lines under ground (cost?) I feell that based upon the past our power is dirt cheap right now (remember the 70's?) A 20% increase in power and a 20% decrease in solar costs may make things more practical? If I spend $20'000 extra right now(?) to save $1,200 a year now (?) It might not look too bad in a few years if the price of power goes up.
*
Some thoughts about your situation:
If you choose to go solar, consider running a 50 amp 220v subcircuit from the shop to the house (are they 500 ft apart ie: both on the same driveway?). Then you don't need a backup generator, and if net metering comes to TN, you would be all set to make $ on any excess power.
I ran 1400' of underground cable at only $1/ft for the trenchwork. A neighbor had a small Kubota tractor with backhoe, and dug the trench (3ft deep) and backfilled it for $1200, the rest was for a sand bed.
The power company put a high voltage line in 1000' to a transformer. In New York they have to go 1000' for free IF there are two houses (100' otherwise). I then ran 2 secondary lines, one to each house. The joke on the power company was that the other house was solar, and never used the power.(4 years later her meter still reads 000000).
See a recent consumer reports about refrigerators, some of the name brands now are nearly as energy efficient as the Servels but only cost $800.
My neighbor spent 6.5K$ for her solar system, (includes a fancy Onan generator and Trace inverter).
She has wood heat, propane hot water, fridge, cloths dryer and backup heat.
Her PV system supports:
Compact flouresent lighting
TV, Stereo, VCR
Standard washing machine
power tool use (somewhat limited)
60ft water level well pump (Special, efficient, 110V
type)
Exaust fans
Small kitchen appliances
other small appliances
She almost never uses her generator. (2-3 times/year) to top up batteries (if >1 week of cloudiness)
She has used her generator for extended use of large power tools (planer, joiner, tablesaw) when she needs to use these tools on site.
*Don:Thanks for the additional info. Based on my personal use of PV for several years and the experience of others whose systems I have either designed, installed or helped maintain I'll try to give some helpful advice.First, there is a lot of snake oil in the PV business so you really have to do a lot of filtering to sort things out.I'll start with what PV is Not:-It is not pollution free. It just shift pollution from your property to the manufacturing facility for the panels, batteries and other gear. Also, for a domestic application there is no getting away from handling and dealing with the hazards of batteries.-It is not maintenance free. There is at least annual maintenance of connectors, batteries, and other equipment. Depending on weather and UV damage maintenance can be more often.-It is not a one-time expense. Most PV panels start deteriorating in about 10 years. Then their power output declines steadily at a rate that seems fairly individual. Storage batteries need to be replaced based on useage and weather conditions.-It is not cheap. If you are in an area with excellent sun there is a possibility of subsidizing your system by selling back to the local electric utility. But even then it is cheaper to extend the electric grid than to install PV in nearly all cases. All the successful systems I'm familiar with are for remote sites where the nearest commercial power is at least 10 miles away or geographically unobtainable.-It is not key in getting back to a simpler life style. Upon examining the lifes of those who say that it is one finds that they have changed their total lives, including reducing their total electric consumption. Most of us don't want to waste, neither do we want to deprive ourselves of what electic technology has to offer.-It is not efficient. One needs to find other ways to heat the structure and for refrigeration and cooking. Typically either propane, oil or wood are used.What PV Is:-It is the best way to get limited quantities of electicity to remote areas where the cost of extending the commercial grid are too high and supporting full time generators is not feasible.-It is quiet. So operation in remote living does not disturb the esthetics that draws people to that life style. Or, is their refuge if they have little choice.-It works well when blended with adequate generation. The generator(s) power heavy loads like pumps, welders, saws, washing machines. The PV takes care of lights, entertainment radios, ham radios, TV, Stereo, etc.Based on the above sketch I think for your geographic area and use you would be best off to buy an adequate diesel generator to use as a backup power source. (Be sure to run it frequently to keep it in good condition) Then invest in as efficient appliances as possible to minimize your electric bill.Hopefully this is helpful. Any more questions just ask.
*
Don,
Tennesse does have net metering, I know of some folks in southern Tenn. that use a wind turbine/pv setup and actually get a check from TVA each month. Isn't THAT a nice thought!!!! Also, do you have water available? Micro-hydro systems have come a long way in the last decade - just a thought.
Fred B is right in that the pollution of PV is displaced, but even so, the total energy cost of PV vs. traditional coal or gas utility is much much less. It is not for everyone, but then some of us don't mind normal maintenance - it is part of our connections to the world in which we live.
Good luck and here's to life without utility monopolies.
Lisa
*
Hi Fred,
Just a quick one for now. I live on the grid but generate ofer 75% of my electricity from solar (neighbors have tall trees that cause me problems in the winter). At 700Ft. solar is cost effective with the grid. You may want to start small where you live now and expand when you build your new house. Buy the cheapest panels in $/watt and allways buy 2 at a time so you could go to 24V even if you start with 12V. If you are going with an AC system I would reccomend a sine wave inverter such as StatPower or Trace. They are much more effective at running motor loads. Use LP or NG for your dryer. Staber makes the best washer. PV shingles are expensive and have a lot of interconnects to go bad.
wwwihomepower.com is a good info source. Golf cart batteries are good to start with. Don't get "self regulating" panels and do use a charge controller.
*Don, Ron, Lisa:Sorry I haven't replied earlier but I've been out of town.As this posting has shown there is a lot of room for discussion about PV energy. What makes some discussions difficult is the snake oil and the lack of clarity about what decisions are made for philosophical reasons and which are made for economic ones.In this particular posting I've tried to stick to the economic factors. Seldom,especially for the kind of loads I envision from Don's explanation, is PV an economic choice if grid power is available. Even if some can be sold to the local electric utility the income typically is not enough to justify the expense. That is; the rate of return on the PV investment is less than what could be obtained by other investments.Under current technology the economic fact is that PV is a relatively inefficient method of electrical generation. There is a good deal of reasearch going on to make PV more efficient so maybe sometime in the future we can all go off the grid.
*
Does anyone have any observations on using solar energy and possibly propane to become grid in dependent. Right now the cost of this system is somewhat high. Does anyone have any thoughts on when or if this system will become cost effective.