Hello,
Live in Bridgeton NJ looking at solar power for the house have a dutch colonial with the back of the house facing the southern exposure on the highest point in the area.
Spending $80.00 per month for electricity. NJ will pay 70% of the conversion to solar power. The question is can I save money by doing it myself or should I leave it up to the installer. Has anyone done it and is it really worth it.
Thanks let me know.
Jimmy B
Replies
Jim,
I and my wife are pretty handy. Built our 8000ft log home from scratch.
just the two of us.
When it came to the solar, we were glad to give it up. First, its a big job. The panels are large, the racks are large, the batteries are heavy, the inverter and charge controller are quite tricky to wire, the grounds are extensive and run everywhere, and the various pieces are so expensive that I didn't want the financial responsibility of screwing them up.
I also think he got better prices on the equiptment than I could have.
So, we have 24 panels, 16 batteries, an 11,200 watt generator, and about a ton of wires and guages.
Money well spent to have it done.
Stef
Thanks stef,
I have a company comming out july 25th to inspectmy house to see if it is a good solar house. Once I get the quote I would like your opinion on it, if it is a fair estimate. If that is not a problem with you.
Thanks again for your input let me know if I can get your opinion on the estimate thanks.
Jimmy B
I'd be glad to help.
Just remember, costs vary by a lot, depending on region and, whether or not the guy wants your job.
My bids varied by 100%, and the low bid was just great.
I'll help if I can
Stef
Just curious what you and your wife do in your 8000 sq ft home, play tennis? I don't think I've ever been in a house that large and was trying to think of what 2 people do with all that space. I can think of a few things I'd like in my house (a large library, solarium, swimmin' pool), but then I think about having to clean those rooms and the public library and pool look more attractive.
Hard to know where to begin, given your and the subsequent post.
Our house IS large, because we have many desires. We lived in Hawaii where small houses are pretty much all there is so we decided to hold nothing back.
So, when we designed this one we incorporated all features we wanted.
It is spacious, not that many rooms, but you might have to raise your voice to speak from one end of the living room to the other.
We have many interests, cooking, woodworking, stained glass, gold jeweler making , model railroads, so all space is spoken for.
More details if you desire.
As to the cost of the system.
Junkhound's figures don't jibe with ours.
We installed in two increments. A system with our ultimate charge controller and inverter, and a small rack with a4 120 watt panels.
That one, including installation and wiring and 8 batteries was 12,000.
The second system, was 21,000.
It had a 12000 watt generator, 20 more panels, 8 more batteries, two large pole mounted racks, all the attendant wiring and stuff (I don't actually know what all the "stuff" was)
Oh, yeah, the generator is a 240 volt unit which feeds into a large transformer to send lower voltage to the charge controller, and a separate feed to a few boxes so I can have 240 for my shop machines.Nice to have such a luxery.
So, 34000 for the entire system.
Now, we are completely off the grid.
BUT, above us a ranch was subdivided into 40 acre parcels. And if they ever bring power in, we wil be selling beaucoup watts back to the company.
I figure 10 summers, or less and our system would pay for itself.
Not that you could necessarilyl do that, but it might be a consideraton.
That is our system, and it provides all the juice we can use, in a large house, with all the accoutrements.
Let me know if I can be of further help.
Stef
Methinks if you disconnect your generator, you wont be able to make your morning coffee after a day or so.
By your figures, you paid $33K for 2.9kW peak solar, if they are not 20% eff. tracking arrays (doubtful), you are getting less than 10 kW-hrs per day for an investment cost of about 45 cents kW-hr for the solar at 5% return on capital comparison. The generator provides power at about 6 cents kW-hr for fuel, so real easy to get your numbers mixed up and think your solar is a great savings, esp. as all is tied into the low voltage bus. Buy yourself a PICO A/D converter that hooks into you computer parallel port and instrument your system to see what is really happening.
Solar is indespensible for space and telemetry -- for terrestial homes, try disconnecting the generator and see what happens.
BTW, the array referenced was on Haleakala peak next the the AF observatory, taken down last month.
good points all around...Solar energy has its place in remote locations where piping in energy is very expensive. IIRC, anytime you're more than a few miles from the grid, solar or other renewables make a lot of sense due to the high cost of stringing all that wire. It's also pretty location-specific. In CA or much of the southwest, there is pretty steady insolation all year. Thus, it is easier to cover most of your energy needs with solar heat/power than elsewhere, where the insolation/weather patterns are more variable.Up here in the Northeast, insolation can vary from the maximum in the summertime to 20% of that in the wintertime. Thus, spaceheating with the stuff up here is pretty much out of the question, unless you arrange a lot of arrays vertically, have a very tight house, etc. For me, it's a matter of allowing my boiler to take the summer off, nothing more.On the other hand, PV does have its place in some urban areas simply because the cost of piping in more energy is very high, there are tons of unused roofs, there is a peak in summertime electricity demand for AC, etc. I am sure that if you took all the siting issues for a new power plant (and its fuel supply) into account that solar energy starts to look increasingly atractive. Naturally, conservation (window films, etc.) is even less expensive.However, heating DWH is the most natural application of solar energy, and China is racing ahead in this category with something like 76% of the worlds solar collectors being installed there in 2002, most for DWH, IIRC.Another application that more residences and commercial buildings are getting into is recovering waste heat from the water that flushes out of them. The GFXTechnology HX I installed in my basement should stretch our supply of DHW quite a bit. Such HX's are inexpensive, easy to install, and very effective.
Actually, we have an Outback charge controller which has a cummulative meter on it. during the shortest days of winter, during late December, it produced 6kw a day. Which, with the way we live is almost exactly our daily consumption. during the summer it produces more than twice that. We have never had the generator kick on by itself. I run it once or twice a month just to keep it's battery charged.
I use it for the 220V as I mentioned, but run it for only a few minutes when the planer or joiner are running.
Be that as it may, though, it was never a matter of economics. Where we live the closest poles are 4 miles a way, and we were quoted $10,000.00 PER POLE to run it in. Much cheaper to buy the solar.
I do agree with you, that there is no economic justification for the solar, and we didn't do it to be green (God forbid), just so we would have light.
Stef
Congratulations!
I thought I was frugal, but getting by on 6-kW/hrs per day is a real achievement. With that low of consumption, you definetely do not need to run the generator. The numbers definetely compute with your updates.
My own consumption is about 5X yours, about 30 kW-hrs per day in the summer, up to 3X that in the winter (electric heat/HP).
Way off the grid is definitely one of the reasons for solar.
In 1980, one of the missile basings (4600 sites) was contemplated for southern Nevada/Utah deserts, about 250 megawatts. A new power plant would have needed to be built.. Even in 1980, solar concentrators look an attractive alternative in that situation, due to other power line costs like EMP and nuclear effects.
You guys must have cheap electricity! In central California I'm paying on average 13 cents per KWh. Our 3KW PV system is going in this week. Grid tied (no batteries). Break-even will be at around 13.5 years, including financing costs. The panels are guaranteed for 25 years and often last longer. The numbers sure work for me!
Now, if you are talking off-grid I'd have to agree that it is not cost-effective. Costs of battery room, initial battery buy and regular replacement (I seem to recall every 5-7 years) far outweigh savings.
That 25-year guarantee sounds good, until you look at the history of PV equipment manufacturers. Most don't stay in business longer than a few years, and a warranty from a bankrupt company is not very useful. The exceptions are the Japanese companies.My experience with consumer-grade equipment in constant outdoor exposure is that it gradually deteriorates until the day it's damaged by wind, hail, ice, lightning, etc.. I seriously doubt those PV panels and their associated wiring will be functional after ten years. Owners of PV systems with batteries also need to to factor in the cost of replacing them every 3-5 years. Not a minor expense.IMO, PV only makes economic sense if it's managed and maintained as a utility, with the output added directly to the existing grid. Renewables like PV and wind simply don't scale to the point where individual home owners can use them and come close to recouping their investment.
Kayocera nad Sharp have been around a loooong time - I'm not too worried about them going under. I do agree about off-grid systems - the batteries make them very difficult to justify. Our system is grid-tied - "with the output added directly to the existing grid" as you suggest.
Not sure where you are located. In central CA we have the second highest electric rates in the country, plus lots of sunshine. Those two factors make the payout equation work.
No arguement on wind-generation .
I'm not sure that a utility has to be directly involved to achieve scale and to recoup investments, though it helps for sure. Direct-to-consumer grant programs seem to achieve quick responses, with most states running out of grant money in a matter of months.I also agree that large-scale deployments such as across department store roofs, parking lots, and the like are likely to have the lowest installed cost. However, are the mounting options were the highest-cost component in the whole installed-cost equation? What about the balance-of-plant? With the cost of the electronics plummeting, just how small can an installation be, yet acheive minimum-efficient-scale?One model I have seen work in MA very well is larger co-ops buying equipment, qualifying installers, and having a go at getting stuff installed all over the state. That way, you get many of the benefits of economies of scale and the proper installation quality to boot. All of the systems, as far as I know, are grid-tied and only supply a portion of the total power needs to the building they serve.One attractive feature of PV systems is that their power curves usually coincide with the peak demand curve of the electrical grid. One datapoint (CA home featured in Home Power) showed a near-perfect peak-peak alignment on an array that was facing West as opposed to South. A south-facing alignment apparently had the array peaking "out of phase" earlier than the power peak demand curve, though with 7 percent more output.
Edited 7/18/2005 10:51 pm ET by Constantin
Most utilities are good at planing and maintenance, two activities that will elude the typical home owner. The mini PV system will be fine the first year, after that it will depend on regular maintenance to keep it operating. Poor or no maintenance will cause it to deteriorate pretty quickly. People are too busy to clean their gutters these days, so why should we expect them to perform regular maintenance on a roof-mounted PV array?
Interesting, what kind of maintenance are required on a grid-tied PV system? The only things I can think of are: 1) Clean the surface of the PV system 2) Inspect the exterior wiring/mounts 3) Inspect the intertie electronics.When arrays are sloped as much as they are around here and with all the rainfall we get, they shed all normal airborne debris. A good datalogger then gives you a hint as when to clean the PV surface. A yearly inspection of the wiring and the structure should do it as well, though I doubt most homeowners can be bothered to do it. The electronics usually monitor themselves...So, your point is well taken with regard to utilities doing a better job of monitoring their network, doing the PM, etc. On the other hand, the enthusiast HO that goes through the trouble of installing a PV system is also likely to be motivated enough to ensure its proper performance over time. However, as PV systems move into the mainstream, less hand-holding and maintenance can be expected from homeowners. Perhaps the grid-intertie systems can be set up to be monitored by the utility? Any statistically-significant drop in PV output could then prompt an automated call/e-mail to the HO to get their array cleaned and/or inspected. Just a thought.
Concerning PV module longevity: I'm off the grid, and purchased my first PV module (a primitive ARCO module, 33 watts) in 1980. Maintenance = zero. It is cleaned by rain and snow. It is still putting out power at the same rate as the day it was installed, 25 years later. I have no doubt that PV modules built today are at least as durable as, if not more durable than, my first ARCO module.
Martin Holladay
Congratulations - 25 years? You must be getting close to break-even on those PV panels ;-)
There are many PV systems around here which have had their panels going over 20 years. The batteries last 10 years with average maintenance. Used to be that equalization of the batterie4s was an owner initiated thing. Now, my charge controller does it automatically once a month.
There is no maintenance on the panels.
All wiring is out of UV exposure, and out of rancge of all but the most determined rodent.
I don't think your views are consistent with my and others experience here in NWestern Colorado.
Stef
As I understand it short battery life is partially caused by the short sighted corner cutting when buying the batteries for the initial installation, not buying large enough or as many as would make an optimal set.Short of battery capacity the batteries installed have to be more deeply discharges more often than is most economical. Whereas a larger storage capacity would allow shallower discharges and fewer of these cycles. Both cases tends to greatly extend the useful life of the batteries.I also note that it is not infrequent to see people installing $6,000 to $12,000 backup generators and associated switch gear on the off chance that they might need power when the POCO is unable to deliver it. Most POCOs have a delivery rate of close to 100%. Most don't loose power for more than a few hours in a year. Maybe a few days every ten years or so. Many of these installations, IMHO, are overbuilt as standby power. But the general willingness to spend this sort of cash for such a rare event could be viewed as justifying the cost of the batteries on an PV installation. My point being that solar installations without batteries are touted as being close to break even but if they threw in the batteries they could buy for the price many spend on a large backup generator system, possibly still buying a much smaller generator as triple redundancy, they could have the best of all possible worlds. Another point to consider is that the PV panels on the roof are shading the roof and saving you money on AC. A significant savings in the sunnier portions of the US. Where PV is also most efficient due to the number of full-sun hours every year.
Allow me to quibble and insert a shameless plug for some information I put together on my web-site. The life of a battery is governed by a number of factors, but even the best batteries have a finite life as the cells invariably self-destruct. The thicker the plates, the longer the life, all things being equal. Thus, weighing a battery alone will tell you a lot about its potential life.
The Depth-of-Discharge is another big determinant on the life of the battery. Depending on your application, different DoD's work their magic in different ways.
Battery construction (flooded vs. gel vs. AGM) and the charge source are another big factor. Big Wet cells are great for longevity, but take a lot more juice to charge than an AGM. On the flipside, AGMs are more fragile and require more care when getting charged or you'll blow the electrolyte and have a dead battery.
Etc. Have a look at my pages (which need to be updated, sigh) and have a laugh. Cheers!
Well, there are only two of us, and everything in the house runs on gas, except the reefer, lights, and the boiler and pumps. But there is one pump(small and quite efficient) for the entire house, and we activate only a zone or two for the part of the house we spend time in. Our hot water comes from the boiler by way of an indirect tank. Also, the house has lots of south facing windows, so we have lots of light and solar gain, plus all the light reflecting off the snow.
Lastly, we go to bed early in the winter, and we are nutty about turning off the lights.
Stef
You are fooling yourself to think that you will every recover your initial costs, esp. at a $80/month kw-hr usage.
Lets say you build a 2 kW peak tracking system, in NJ you will get maybe 100 kW-hrs out of it a month in the winter, up to 300 kW hrs in the summer. At 10 cents kW-hr, that is $10 to $30 month. I doubt you will build a tracking system, so the kW-hrs will be much less.
Total DIY the lowest cost for even surplus cells is about $5-8000 for 2 kW.
At even 5% interest, that is $33 month, so you are constantly losing money even for TOTAL DIY.
Maybe OK if no grid at all nearby, etc.
Last year I and colleagues built and installed a tracking 1.8 kW system on a mountaintop that produced about 20 kW hours per day. The array components cost about $100,000 and produced 20 kW-hrs per day. At 5% the cost is over 65 cents per k/w-hr. Installation and assembly labor other than DIY would add another $200K or more
However, if it will make you feel good, go ahead, esp DIY. If you have it done, consider most of that money down a rat-hole.
Here is the link on the high priced option. http://compoundsemiconductor.net/articles/magazine/10/8/5/1
Edited 6/28/2005 2:15 pm ET by JUNKHOUND
Indeed, solar for electricity rarely makes economic sense. Consider it instead for water heating, where the initial costs are vastly lower.
-- J.S.
So right John, recall water heating in Israel is over 90% solar.