Why not use a rooftop solar system instead of a backup generator?

My friends here in the Northeast are all running out to buy backup generators now (i.e., closing the barn doors after the horses are gone). The cheapest that I’ve heard for an installation is about $7,000, complete with electrician’s efforts (I was quoted over $20,000 at my house, partly due to there not being a great location or it near the house). The resulting machine will need to be maintained, run every week for a few minutes (very noisy), and will never recoup any of its costs.

It occurs to me that rooftop solar systems are in the same price ballpark ($7,000 to $30,000?). Supplemented by a snow broom, I would think that a rooftop solar system would make a good backup and, for the 99 percent of the time that the grid was working, could help defray its cost by generating useful electricity.

Obviously the solar panels wouldn’t work at night, but it isn’t usually a big deal to go overnight without power. If the well pump and heating system can be operated during the daylight hours that should be enough to keep pipes from freezing and allow the residents to enjoy a modicum of civilized existence.

Here are some questions for the solar pioneers:

  • why isn’t rooftop solar a more common backup power solution?
  • what happens when the grid power fails and there isn’t a massive battery pack? Does the inverter trip off when the voltage to the house drops below 105 or so? And then you run around the house turning off appliances and try to bring the inverter back up? Or there is automatic load-shedding somehow?
  • how much power does it take to run a forced hot water heating system (ignition for the oil burner plus pumps to move water around the house)?
  • what about the roof underneath a rooftop solar system? How would you ever repair shingles? Is it typical to put in a new 30-year roof at the same time that you put in a 30-year solar panel system?
  • how big a system does one need in New England to run the essentials within a house? (essential = heat, well pump, fridge, Verizon FiOS box, router, desktop PC)
  • how many square feet would that system occupy on the roof?
  • is this stuff getting a lot cheaper? Supposedly Solyndra died because conventional panel prices were dropping. Has the price of panels dropped enough to make the overall system substantially cheaper than three years ago?
  • what about all of the tax breaks whereby one used to be able to get one’s fellow citizens to pay most of the bill? Are those still in place? [I think government subsidies are bad, except ones that involve mailing a check to my house.]

I’m wary about solar because it seems like too advanced a technology for a U.S. home. It is so painful to get simple stuff fixed that I can’t imagine what would happen with a technician up on the roof with a Fluke voltmeter.

45 thoughts on “Why not use a rooftop solar system instead of a backup generator?

  1. Whaaaa? $7,000? You can get a little gas generator at Home Depot for a few hundred. That’ll do to charge your devices, run some lamps, heat some water. What kind of suburban hand-flapping twit thinks he needs to completely duplicate the full-grid experience? Stupid tremulous timid panicky helpless dependent rich people. Gahhh. This is why we get such preposterous clowns running the country. No sense of reality at all, stumbling around in a narcissistic fantasy world.

  2. Interesting idea…

    Here’s a good place to start:

    http://www.solarpanelsplus.com/solar-insolation-levels/

    As a rough estimate, you will get roughly 10% of that amount out of the solar cells. If it was Boston in January, you’d get 0.14 KWh per day out of each square meter of solar cells.

    To figure out how much it takes to run your appliances, look at the baseplate ratings, then you can figure it out. Or you can look online. This link might help:

    http://www.energysavers.gov/your_home/appliances/index.cfm/mytopic=10040

    So, take the wattage of each of your systems and multiply them by how much they run each day; that will give you the total number of kilowatt hours you need per day.

    Rough estimates; the fridge will take about 1 kwh per day, the pc (if you use it 8 hours) about the same. The well pump takes a lot of power but only runs rarely, so it probably doesn’t use more than 0.1 kwh per day. I didn’t find any figures on the furnace.

    To get 3 kwh per day, you would need 3 / 0.16 = 18 square meters of panel. That’s roughly a 5KW system, and you can estimate $9-12/watt for such a system with battery backup (http://aladdinsolar.com/pvsystemprices.html).

    Or something like $50K.

    Subsidies depend a bunch on where you live.

  3. At least on my 7KW array in CA, if the power goes out, we have no power when there is an outage. The array feeds to the grid, not to the house.

    You are not generating 7KW when the sun is up. It varies over the course of the day. We have a south facing array, and probably generate peak power 1-2 hours a day during the summer.

    Our roof was almost 20 years old (but in good condition) when we installed the array. Not something I worried about. We relied on our installer’s evaluation.

    I hope you don’t fall off the roof with your snow broom, as the medical costs will completely outweigh any savings.

    So, you’re probably better off with a propane-powered generator for your scenario. That’s what most people in our rural West Sonoma County area do.

  4. Poul-Henning Kamp (FreeBSD, phkmalloc) has installed solar panels in his holiday home and has written a series of articles about it. They’re in Danish but Google translation of the articles are readable. Approx location: “Slagelse, Denmark”, a country of 1000 styles of gray weather.

    To translate costs into dollars: 6 kr = $1. 100 øre = 1 kr. (Google translates ‘øre’ as ‘ear’ in a few places). “a plow man” = 500 kr (the 500 kr bill has a picture of a plow man), “a dog” = 100 kr. VAT in Denmark is 25%.

    http://ing.dk/artikel/123351-solstroem-status-1-aar
    http://ing.dk/artikel/109566-solstroem-for-40229
    http://ing.dk/artikel/110164-223338-kwh-solstroem-i-juni
    http://ing.dk/artikel/112193-solstroem-til-50krkwh

    To translate, prefix URLs with http://translate.google.com/translate?u=

    Your local power supply company might not allow you to send electricity back into the grid, or might pay you almost nothing for it. Home owners association might forbid you from installing solar panels.

  5. Much cheaper still: a small, portable generator for running a few appliances and computers wired to a transfer switch. Call it $3,000 for a nice generator and the electrical work.

    Then use something else like wood or propane for heating and cooking. In other words, don’t try to run everything off of the generator.

    My emergency winter heating and cooking solution is built around propane. Three 20 pound propane tanks, a BBQ grill with a burner on the side for outdoor use, a Coleman camp stove I can use indoors, and a Mr. Heater Big Buddy for indoor heating. That’s for a relatively mild Tennessee winter. Total cost not including the grill I already had was around $400.

    I don’t have a generator. I have a Husky power box ($100) with an built-in inverter and a 700 watt Xantrax inverter ($30) I can connect to a car’s battery. Beyond that I have candles, flashlights, and LED lanterns for lighting.

  6. Generator/propane enthusiasts: I know that I could get a portable generator for fairly minimal $$ and keep it in the garage. But as noted above, that’s another machine to maintain. I don’t want to add the task of “haul generator out of garage and run for 5 minutes” to my weekly plate.

    The previous owner put in a $10,000 propane-powered Viking range. It can crank out quite a few BTUs. The issues with using that as a heat source include (1) distribution (not obvious how the heat gets to the downstairs level), and (2) safety (manufacturer specifically says not to use it as a heat source; does it put out more CO than a specifically designed kerosene or propane heater?).

    The fact that the well pump requires 230V and is hard-wired to the panel complicates matters. Also the heating system. I’d actually be reasonably happy if I could run just the well pump and the heater for 8 hours per day.

    Mike: Thanks for your concern on the snow broom issue, but I could probably reach most of the array simply standing on a deck and using a broom with a 20′ reach. There would be no need to get up on the roof.

  7. The reason Viking says not to use the range as a heat source is because you would exceed the duty cycle it is designed for, and also because if the burners don’t have a pot to act as a heat sink, they can overheat.

  8. Phil, I’m not sure why you’d need to run the generator every week. That’s certainly not something most generator owners do. Maybe that advise is for a standby generator?

    For propane heat, the Mr. Heater units are portable. They can run on either 1 pound screw-in cylinders or can connect to 20 pound cylinders like the ones you use on a BBQ grill via a hose. You’re supposed to keep the big cylinder outside, but I have a friend who heats the upstairs of historical home with it inside and has for years.

    The Mr. Heater Big Buddy has an AC/DC fan to help distribute the heat. The Big Buddy is rated to heat a 400 square foot area. Cost is about $150. Available at Home Depot or even Amazon.

    Carbon monoxide detectors are a must. Our smoke detectors do double duty as CO detectors, so we’re covered.

  9. You don’t need to run the portable generators every week. With a gas stabilizer, you could run it every couple of months. I recommend Briggs and Stratton engines over Honda as I’ve had better luck with them after months of no use, such as a snowblower.

    There are reasonably priced portable gas-powered generators that have 220v outlets.

    I would not use the Viking range as a heating source. You can get a gas stove with exterior air draw installed for about $3k. We’re happy with ours.

    If you need emergency power, then a portable generator is still the most cost-effective and convenient means. Solar still costs too much in terms of hardware, installation, maintenance and space around the house.

    An additional advantage of a portable generator is the portability. You can have power at other locations when necessary. You can help a neighbor. In the case of an evacuation, such an environmental disaster, it’s useful to have in addition to car inverters. You can use it for other things, such as camping or at a hangar, or your favorite activity: tailgating at football games. Many locations in MA and CT were out of power for several days. With a generator, all you need is too keep adding fuel rather than hoping for sunny days.

  10. Les: Why run a generator every week? That’s how the standby ones are programmed, as I understand it. Most engines like to be run regularly. Certainly at least once per month in the case of airplane engines.

  11. I have a 3.5K watt generator that cost $1000 in 1999. I run it least once every year and have no problems with it at all. (Briggs and Stratton engine). Just add a little gas stabilizer to your gas supply as has been mentioned any you should be ok.

    Make sure you hook up a transfer switch wired to about 6 circuit breakers. Then when you get a power outage you can switch those circuits to your generator.

    I have 2 fridges, 2 gas furnaces, a freezer, and living room lights (and a tv). Remember your cable will usually be out with the downed power. So you can get a dish, which isn’t affected.

    All this cost $1000 + $200 + electrician to hook it up ($200). It’s been well worth it.

  12. For a Solar System to function as a “backup” system… it needs a form of energy storage.. massive amounts of storage… viable solutions.. fuel cells or batteries.. cost of both is going to far exceed any generator…

    Usually folks who use Solar, use the grid as the “backup” , since storage is very expensive and many have NG using generators as a backup.

  13. Many people in my office got solar, so I think I can answer the roof question. McMansions built in the last 12 years require additional support and bracing (sometimes a couple of days of work) to handle the weight of the panels on the roof. Most people do not have their roof replaced. If the roof needs repair the panels need to come off in that area. Since the sun is not hitting the roof under the panels, the roof should last longer.

    The reason tied-in solar is popular in California (besides the Green factor) is tiered electrical pricing. After the first ~270kWh, the price goes from .13 to .15, then to .23, then to .27 and up to $.30 per kWh. Because of net metering law, consumers can sell electricity back to the utility at the wholesale rate and reduce their net energy consumption enough to move several tiers down in the cost per kwh.

  14. Think about a gas lawn mower. You let it sit all winter and it’s fine when you need it in the summer. You only need to run the engine every few weeks if you want a high probability of starting with one button push(or pull). If you’re willing to forgo 16 hours of electricity (only 8 hours/day). I think you could spend the time to mix the gas, re-tighten the spark plug and wheel the generator out to the edge of the driveway. The real issue is then, prepping it for long term storage when you are finished; draining the gas, loosening the plug, giving a quick shot of oil into the cylinder an then wheeling back into the garage. If you only need electrical standby power occasionally, and infrequently, then it is by far the most economical and easiest solution. If you were someplace where the power outages were frequent, or you needed back up power immediately, then maybe other options would make sense.

    You still need to worry about power distribution from the generator…but you could go whole hog and wire in a transfer switch to the main breaker panel. Wait a few months and the electrician will charge a reasonable rate. (2-4 hundred including the switch)

    The entire setup, generator, standby switch, gas storage and installation should run you less than a grand. This wont get you instant on 100 amp service, but it sounds like it will get you more than you are actually asking for.

  15. I looked at backup power for my home in central Texas. The system I liked most was around $15K installed. It would turn itself on and run for a few minutes every month even if it wasn’t needed.

    Given our short winters I decided an outdoor grill and fireplace would do, and I’d use the $15K to go stay on the Gulf Coast for a week.

  16. Solar sucks…: My experience with small gas motors has not been very encouraging. Getting a chainsaw to start after a winter off, for example, has ended up requiring expert intervention.

  17. Almost all solar systems don’t provide standalone power, they only suplement the power coming from the grid or push power back into the grid if you can’t use all they produce. By design they shut off when the grid shuts off.

  18. “Obviously the solar panels wouldn’t work at night, but it isn’t usually a big deal to go overnight without power.”

    I’m not sure why not having power at night isn’t a big deal (the generator works night and day).

    For a given amount of power, I suspect that a generator is going to be cheaper and easier to install.

    I know somebody with a “cabin” (a small house) that has a small solar collector and a bank of batteries and an invertor. He also has a generator for when the bank runs out. He uses a propane refrigerator. He’s set things up so that his demand on electric is low. The solar works well in the summer but wouldn’t work very well in winter (in Maine).

  19. You’re way over-thinking this. Get a portable generator, hire an electrician to hook up a sub panel to your main panel so you can plug it in and your done.

    Start the thing up once a month if you think it needs it. I’ve had one for 11 years sitting in my garage, and I rarely start it. If for some reason it doesn’t start, all that’s needed is a new spark plug.

    I’m going to go start mine right now 🙂

  20. For a standby generator (the kind that starts automatically the second the power goes out) you may need to start it every week. For an emergency generator you power up by hand that isn’t necessary.

    Since you already have propane plumbed into the house there’s another option for heat. Install ventless, in-wall propane heaters as needed. Home Depot and Lowe’s sell them and can probably introduce you to an installer.

    http://www.amazon.com/PROCOM-Blue-Flame-Vent-Heater/dp/B002NVGJO0/ref=sr_1_14?ie=UTF8&qid=1320698102&sr=8-14

  21. My folks live in Joplin, Missouri very near the path of the recent tornado. They didn’t have much damage, but they were without electricity for 14-days. A few years back there was an ice storm that resulted in a week-long outage and they bought a cheap $700 gasoline 5000-watt generator from Lowes.

    It took me two days to get to Joplin from Oregon after the tornado where I found the generator non-operational. A helpful neighbor had tried to diagnose it by removing the carburetor for disassembly but failed to get it back together.

    I reassembled it properly and fired the generator up with liberal amounts of engine starting fluid (ether essentially).

    It ran for the next 14 days 100% of the time except for a few brief stopages to check its oil level (it never needed any added). Although not recommended I even managed to refuel it twice a day while running. It was very hot and humid after the tornado and air conditioning was a necessity for my folks.

    Instead of fancy switching power distribution we just ran extension cords into the house and plugged in the necessary items (for my folks: fridge, air conditioner, coffee pot, TV).

    After the house got hooked back up to the grid I serviced the generator (new plugs, oil, and air filter), drained the gas, and put the remainder of the gas in my truck.

    Lessons learned:
    * You can get by just fine keeping things simple.
    * Cheap generators do a fine job.
    * Don’t store your generator with gas in it (gas nowadays contains a lot of various volatiles that boil off quite rapidly).
    * Don’t let helpful neighbors help with technical tasks.

  22. If you’re using a fuel stabilizer like STA-BIL then you shouldn’t have any problem starting a chainsaw after a winter off. I use a double dose (per the product labeling) in 93 octane fuel for all my small engines and the seasonal use has never been a problem. This has been true for my lawnmower, snowblower, chainsaw, trimmer and leaf blower.

    For the occasional use engine like a generator, it’s better to drain the tank, run it dry and squirt some oil in the cylinder. Use your lawnmower/snowblower fuel when you need to run the generator when the need arises.

    Unless you expect very frequent power outages, a gas-powered generator is going to be your most economical and easiest option.

  23. You already have a large propane tank for your range. You need to be thinking about propane generators–not gasoline. You don’t have the fuel spoilage and fouling issues. Don’t let your bad experience with a tiny, possibly inexpensive(consumer model) chainsaw engine cloud your judgement. Millions of Americans successfully use and abuse small engines reliably every day. Unless you’re running a mission critical data center or medical life support out of your home, you can live with the possibility that your generator doesn’t start. If you faced with the options: a) no electrical utility service, and b) generator that won’t start, I’d say your chances of being able to remedy scenario b, by calling a small engine mechanic, are many orders of magnitude more likely than being able to affect scenario a in any manor.

    Here is an Aluminum enclosed, sound insulated, 17kW propane/natural gas generator with transfer switch for $3772.

    http://www.electricgeneratorsdirect.com/Generac-Guardian-5886-Standby-Generator/p4795.html

    As someone else pointed out, you can spend many nights at hotels for the price of an installed generator. If you’re intent on riding out power outages at your own compound, a generator is your best option.

  24. I work for a company that makes solar panel inverters to convert the panel’s DC to AC. Regulations require that if the grid voltage goes away, the inverter must shut down and stay down until grid voltage has been back for 5 minutes. As a result, a grid-tied solar array would be useless for being a backup power source.

  25. Buy a generator. Solar is practical in remote sunny locations with no other options (outer space). Otherwise it’s a novelty for religiously green types. Snow brooms… that’s a joke, right?

    Generator should be 5kw-10kw ($500-$2000). 5kw (20 amp bkr) is sufficient for my forced hot water / oil furnace, refrigerator, TV, and a few lights. Install a transfer switch to disconnect from the grid and align the generator to your breaker box as the sole source of power. Makeup a umbilical (~10 gauge/4 conductor) to plug into the transfer switch and run to your best generator location (keep it less than 100 feet). Generators are noisy and the exhaust is not compatible with life. Think: downwind but still accessible for refueling.
    Drive away cost = $2500-$3500 or more.

    Tip: make a voodoo doll in the shape of a snowflake and stick pins in it. Keeps the evil spirits away. And with any luck you’ll never have to use the generator.

  26. You already have a gas generator. Your car(s) probably has a 35 to 50 amp 12V alternator and a “buffer” battery. You can run a 500 Watt inverter (or may be even 1 kW for short periods). budget that power – it should be enough to survive – and use the jump start cables. Hopefully you can take care of the heating issue with a fireplace and/or a wood stove as 500 watts won’t be enough to heat a room in winter.

  27. Q:why isn’t rooftop solar a more common backup power solution?
    A: Paradym Mentality. Backyard pole mount is easier & adjustable.

    Q:what happens when the grid power fails and there isn’t a massive battery pack?
    A:The entire system powers down to prevent backfeed into grid…unless you have enough batteries to run your (isolated-sub-panel) critical loads.

    Q:Does the inverter trip off when the voltage to the house drops below 105 or so? And then you run around the house turning off appliances and try to bring the inverter back up?
    A: The Hybrid Inverter, or Seperate 2nd Off-grid Inverter takes over seamlessly to run critical loads in sub-panel.

    Q:Or there is automatic load-shedding somehow?
    A: A charge controller dissapates, a dump load (heating element) burns off excess, or firmware distorts frequency if the batteries are full during an outage to prevent overcharge. When the grid is in normal operation any excess is sold to the utility. Again ….batteries required.

    Q: how much power does it take to run a forced hot water heating system (ignition for the oil burner plus pumps to move water around the house)?
    A: Every appliance made has a badge or sticker (usually black or silver) listing the device’s maximum power draw in Amp & Volts, or Watts. Most forced water pumps are about 150W or so. (150 x #of pumps + burner = ?) Is the burner electric, LP, or heating oil?

    Q: what about the roof underneath a rooftop solar system? How would you ever repair shingles? Is it typical to put in a new 30-year roof at the same time that you put in a 30-year solar panel system?
    A: Always a good idea to do improvements at the same time. Even better if you have room for a pole mount in your backyard. Roof mounts are usually two sets of long rails that attach with “L” shaped feet to a roof. The panel’s frames mount to the long rails, it pretty easy to add a water proof flange, standoff or remove after installed. 30yrs is a shorter life than most panels, their warranty is for 25yrs. Seimens 70W panels made in 1958 are still making 55W today.

    Q: how big a system does one need in New England to run the essentials within a house? (essential = heat, well pump, fridge, Verizon FiOS box (550W), router, desktop PC)
    A: Furnace Fan 900W+Well Pump 1200W/240V+Fridge 900W+Web/Cable/TV/PC/Info 900W+Lights 200W = 4,100 (But I’ll size for 6kW cuz I know you forgot something)

    Q:how many square feet would that system occupy on the roof?
    A: Depends on your goal, funds avail, etc. I’ll assume backup power that pays you back over the long term. Your devices proably consume around this rate:
    Fridge 250W running 15 min/hr, Well Pump 100W running 15 min/day, 1800W 2 hours watching TV, & web surfing non-stop & simutaneously, 1000W Lights (30 CFL’s or 10 100W incandescents for 5 hours) =apx 9kWh
    9kWh/2.99 NREL Boston solar LOW= 3,010W PV array requirement.
    about 268 sq. ft.

    Q: Supposedly Solyndra died because conventional panel prices were dropping. Has the price of panels dropped enough to make the overall system substantially cheaper than three years ago?
    A: Yes, dropping everyday. It’s unfortunate American companies innovate, while the Chineese emulate with a lower cost & quality product. There are still plenty of quality panels made in the U.S., Europe, and even China.

    Q: what about all of the tax breaks whereby one used to be able to get one’s fellow citizens to pay most of the bill? Are those still in place? [I think government subsidies are bad, except ones that involve mailing a check to my house.]
    A: The Federal 30% tax deduction (No Check) is in place for business & residential until 2016. State, Local & Utility Incentive are listed at http://www.dsireusa.org <—Do it.
    Parity is near, if subsidized like fossil fuels, parity would be now.

    System quote:
    BPS XW6kW/12kW Surge w/ 8kWh of AGM battery storage & 3,150W Solar PV
    $20K+$2K Install
    $22K-30% Fed or 6,600= $15,400
    0 moving parts, 0 maintainence, 0 noise
    OPEC, Pandemics & Fuel Shortages are less of an issue.

    Generator: $5,000 8kW (No surge) Generator+ $1K install = $6K initial
    Fuel : say $42 day 1/2 gal/hr + 1/16 gal. weekly maintaince run.
    Earthquakes disrupt gas lines, Fuel tanks are dangerous &/or fuel gets old, Ever been to a gas station during a hurricane. Looters hear your generator too. You mean it din't start, in ran fine back in '02?
    A generator can also be integrated with the solar/battery system with auto-start/stop based on battery volatge.

    Mike Swenson
    507 227 2923 ….if you're serious.

  28. I think the real reason the Viking isn’t used for heat is that, when you lose power, you lose the automatic electric restart. If the flame goes out (think of a pot boiling over), you’ll be filling your house with natural gas. Then you’d better hope the power doesn’t come back on.

  29. I read a big Survival Blog (aptly named survivalblog) and EDC sites, more for the preparedness and camping info they have, rather than how to act once the SHTF, but there are a surprising amount of people on them who heartily recommend Solar Power. If you dig around you can probably find plenty more posts by people with good experience using it not only in emergencies but also for day-to-day usage – if used, for example, in an out of town cabin.

    Their search leaves a lot to be desired, but this guy’s gone into pretty good detail about his usage with solar panels.
    http://www.survivalblog.com/2011/09/small_scale_alternative_energy.html

  30. Two thoughts until I can look into my files ~ in a few days & also ask friends.

    Germany is the world’s foremost adapter for household solar. The solar gain rate there is similar or less than the northeast. I will send this thread to a German solar architect with whom I am discussing a different kind of project. He’ll find it interesting & may have ideas for you.

    A friend here lives off the grid with full-function computers, TV & lights. His winter heat is wood. A woodstove backup such as Jotl would easily fit into your house – did you say earlier whether you have a fireplace? Added fireplace-inserts can be super-effective heating.

    Hands-on heating can be functional, time-efficient & esthetic. On my house rebuild, we installed woodstoves in the LR & office/shop even though the floors were radiant-heated throughout. Little “stick-fires” postponed the date we turned on the whole system.

  31. I guess I should have said Germany is the world’s foremost adopter & adapter for household solar …

  32. I was recently thinking along these lines. I decided that the most important thing to back up at my house is the oil burner for hot water and baseboard heating and the well pump.

    The oil burner and well pump only fire up periodically, they are not a constant drain of electricity. If you had sufficient battery storage, you might be able to get away with fewer panels set up for the purpose of recharging or keeping a “trickle charge” flowing to the batteries.

    I quickly came to the realization, though, that it would not be cost effective to set up such a system solely for backup in the event that power is lost every few years.

    But . . . what if you rigged up such a system to permanenty run the oil burner and water pump. Take those off the grid full time. In a typical household, water is often run in the morning and evening. In between, the batteries would have the opportunity to recharge. Over time, the small amount of energy savings might add up to defray the cost of this system. Your basic survial needs would be accounted for and you would pull off the grid for quality of life items like the fridge, lights, computer and TV. I could afford to risk losing the contents of my fridge every 10 years or even back that up with a propane fridge.

    Input on this would be appreciated.

  33. Germany calling 😉

    I have some PV on my house – but I can only speak from our very special German perspective:
    We had an energy law that guaranteed more than 50ct/kWhr – but decreasing now to 24ct and counting…
    As we have to pay about 23ct/kWh we for using electricity (100% green or dirty coal/nuclear are nearly the same !) we have reached “grid parity” !!
    So the system changes now: up to now we always fed our solar energy into the grid – earning money. But now we will start using the energy first and only feed it if we don’t need it – now saving money – what is nearly as good.
    As the price/kWh decreased the system prices dropped dramatically.
    We are just a bit over 2000€/kWpeak (2800$).
    Another way is using a storage. But a professional system with lithium power is still very costly – but a self made system with car batteries might be worth thinking of.
    What you have to be aware is the summer-winter difference.
    You don’t get much energy in hazy foggy Novembers…

    Most questions were answered by Michael and others quite perfectly.

    – why isn’t rooftop solar a more common backup power solution?
    -> even here – having perfect financial (not solar) conditions – it’s not really common. But some villages have nearly 100% solar+wind but that’s an exception. I’d say less than 1% have PV.

    – what happens when the grid power fails and there isn’t a massive battery pack?
    Must be a question of your DC-AC converter. As here you can choose and switch between using your own solar electricity or feed in it should be no problem.

    – what about the roof underneath a rooftop solar system? How would you ever repair shingles? You can replace every panel and if removed you can reach the shingles.

    – is this stuff getting a lot cheaper? -> see above…
    when thin film or even printed solar is replacing crystalline solar will get even cheaper I guess…

    What is not really mentioned enough is that every kWhr not created in a coal power plant is a good kWhr !!

    I wich you a wise, sunny decision !
    Frank

  34. perhaps I should add some thoughts about
    “why isn’t rooftop solar a more common backup power solution? ”

    Here in Germany I’d say it’s basically a lack of information and bravery.
    Esp. farmers with huge roof tops have installed hundreds of sqm PV earning a fortune now ! But most average citizens with a little home did not take that risk.
    Some citizen solar plants exist. You can pay e.g. 1000.- and get e.g. 5% rate of return. That’s a way how (nearly) everybody can participate and do something good.

    In other countries it’s also a question of laws and power of utility companies trying to block the small private solar plants.
    Would be a necessary governmental action.
    Many (I heared about 50) countries have adopted our “EEG”-system in between.

  35. Many jurisdictions do not allow any grid tie solar, and are not progressive on any kind of alternative energy. Its not insurable, knowledgable tradespeople are hard to find and building departments are uninformed.

    Technical and financial reasons are not the problem.

  36. You know if you people would spend some money and get the power lines put underground so the trees would not tear down the lines in a storm. Yes I know that doing this may be expensive but it is way less than fixing the lines once or twice a winter and putting in lots of backup generators. Plus the neighborhood will look so much better due to removal of those post and wire nightmares we call power and phone lines…….

    Bill

  37. re. heating with the Viking… Your concerns about CO are probably justified. A proper furnace (such as your oil burner) will have a chimney or exhaust vent pipe. Newer furnaces will have two pipes– one exhaust and one fresh air intake. On the other hand, the ranges I’ve seen have always been ventless. Cooks are encouraged to use the hood fan (which would surely eliminate heat as fast as it eliminated CO).

    Personally, I have my suspicions about “specifically designed kerosene or propane heater[s]” as well. I have friends who installed something similar to the “Blue Flame Vent Free Wall Heater” that Les linked to. The building inspector would not allow it to be installed in a bedroom (hence a sudden bedroom furniture moving project). The heater itself came with all sorts of warnings on it. As for standalone kerosene heaters, they have a tendancy to kill houseplants and smell bad. They actually come with warnings saying “open a window while using”, though I doubt a cold person will be inclined to do this. Similarly, many standalone propane heaters come with warnings saying “for outdoor/construction use only”. I’m not sure why these products get a free pass, when the Viking doesn’t.

    Sorry to babble.

  38. Bill: Why no underground lines? http://www.sltrib.com/sltrib/money/52841657-79/lines-power-ground-underground.html.csp says it can be done for 4-8X the cost of above-ground lines (whose cost is $0 right now since they are already built). Our suburb is tending towards the rural. So it might cost $2M/mile. There are probably about 30 miles of roads crisscrossing the town so that’s $60 million. Divide by 2000 houses and that’s $30,000 per house. I guess when you think about the total installed cost of the generators, running the generators periodically, and maintaining the generators annually it might be a reasonable investment to bury the power lines (assuming that 100% of households wanted to spend $7-30k on a generator). But I’m not sure it would guard against all outages. After all, the grid fails sometimes for reasons other than damage to lines.

    It certainly would look nicer.

  39. “…standing on a deck and using a broom with a 20′ reach.”

    That’s what “roof rakes” are for. Brooms are too heavy/unwieldy.

  40. Stop whining and plan for a propane-powered generator sometime in the future. $800 gets you a 7KW generator from Home Depot, and then pay an electrician to install a switchbox and an outside plug for the generator. Also, pay someone to add a propane outlet at the same spot and you’re good to go. Total cost should be under $2000. My generator gets used once or twice a year, and has more than paid for itself many times over just in the cost of saved food in the refrigerator and freezer.

    Those fancy automated backup systems are nice, but only really needed if short term (a hour or less) outages cause you issues.

  41. Well PHil with your local noteriety maybe you could do something about getting started on undergroud power lines. Yes I know it is diffficult as it took Scottsdale where I live almost 30 years to get fully undergrounded and we still have issues. But the result is startling, our city is very nice and pretty and world renouned for it golf courses and nice areas and mountians views. Fly out some time and take a tour of the city and Talesian West and some golf course areas and mountian areas and see what no power and cable lines does for city….

    Plus in your case much of the current power system is old and in need of replacement anyway so moving towards undergound is only a long term planning.

    Bill
    Bill

Comments are closed.