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So a fairly large 4x4 meter solar panel (that would cost around $5000 to install)

Uhm. What? 325W solar panel, 1.9 square meters per panel, $225 plus shipping. 16 square meters costs $2025, if you insist on exceeding 16 square meters, requiring 9 panels. For 8 panels, it's $1800.

This is not some theoretical nebulous future price, either. This is the "add-to-cart button" price, including tariffs, available this afternoon.

Polycrystalline, so the efficiency isn't great and the warranty is indeed just 10 years, though they will work at some level of efficiency for decades longer than that. The warranty sheet says they'll provide 80% of their original power rating in full sun for 25 years.

No sources for your costs?

First, solar panels are under $0.80/watt, so let's call it 5 kW for $5k, and average 4.92 solar hours per day in New Orleans (1795 productive hrs/year), typical 80% inverter efficiency, so 215.6 MWh over 30 years.

Second, a short ton of coal costs on average $45.66 delivered, and generates 1,927 kWh per ton, so $5k will get you 109.5 tons and 211 MWh.

Third, your whole premise of comparison is bogus, because it doesn't include any supporting costs: installation + inverter for the solar, and the entire cost of the power plant for coal, not to mention all the mining and transport infrastructure investment, which makes a pretty dramatic difference to final costs. A more reasonable comparison would be the Lifetime Levelised Cost of Energy of solar PV vs coal - and coal does pretty poorly there.

Grabbing the back of napkin...

In October, wholesale solar started selling the brand new 14KWH powerwall2 for $5,550. http://www.wholesalesolar.com/... $5550/14KWH = $396/KWH

According to https://en.wikipedia.org/wiki/... The Powerwall has a lifespan of 1000-1500 cycles.

So, assuming 1500, that makes the amortized raw cost of storage = $396/1500 = 26 cents per KWH.

The going rate for uninstalled solar panels is about $2/peak watt. If we figure 80% efficiency, 6 peak equiv hours/day in sunny Samoa, 25 year lifespan, then that watt of solar cells nets just under 44KWH. So $2/44 = adds another 4.5 cents per KWH raw cost for the panels (I'm not accounting for the planned 20% degradation over those 25 years)

So, that's about 30.5 cents/KWH for the raw equipment, not including wiring or racking. It also does not include the electronics needed to get DC panel power to the AC powerwall. (or vice-versa, the cost of an inverter if it is DC all the way) Also not including installation or maintenance costs, wiping off bird poop, or the cost of keeping the backup generators in good working order. It also does not include the cost of mishaps (hurricane, sand damage, broken wires, etc). I lost two panels in a recent hail storm, but those were old panels. The newer generation of panels are built to handle baseball-sized hail.

Installed cost per watt for solar adds about 50%. So, this brings it up to about 45 cents per KWH (not including maintenance or back-up capability).

So, this might be cost-effective, but only if they are paying a very high price for diesel generated power.

It's complex.
Anti-dumping rules have made solar panels in the US amongst the most expensive in the world.
However.
http://www.wholesalesolar.com/... - as one example has panels down at $.89/W.

If you're in an area that needs large amounts of AC in primarily sunny periods, a replacement well insulated roof could do really nice things for your bills by removing the daytime component of your bills entirely, even without requiring any subsidy.

Do you care to break it down? I find it suspicious that you're badmouthing your own company.

Can you show that the ROI, without tax incentives, doesn't happen.

Just looking at hardware (I'll address construction shortly). Here is a 7.8k system http://www.wholesalesolar.com/... for $14,351 That's less than $2 per watt with grid tie equipment. With 5 sun-hours per day, that's 1,060 kWh in 30 days. 15 cents/kwh is $159 per month. That's a 7.5 year ROI on the equipment.

Now the construction. I see often see quoted construction at roughly double the equipment cost. Unless you can convince me otherwise, I think that's ridiculously high and a result of a lack of qualified installers. You need to 1. mount the panels and 2. connect the grid tie equipment. You can get a roof completely reshingled (materials and labor) for $6k. Mounting of the panels shouldn't cost more than $2k. Then there is the electrical hookup, which requires an electrician. An electrician will install a 200 amp panel for about $2,000. Why should it cost much more to install grid tie equipment? So I'll round up and say installation costs should be $5k for this system. That brings the ROI to 10 years.

10 years with NO incentives. And that doesn't count any net metering. As you can see, I take issue with the construction costs. I'll gladly admit my error if you convince me that I'm wrong.

Thank you for the link. Those are raw panels, but yes, that is about what I expected to see.

What do you think of this complete kit:

http://www.wholesalesolar.com/...

I imagine it isn't EVERYTHING that is needed, but it seems mostly complete, at least to include inverter, panels, mounting hardware, etc.

The panels themselves they sell for about $1 per watt, but that appears to be for grade A panels. So they want about $6,400 for all the other stuff besides panels.

This is not a job that I'm prepared to do myself, I have a tall roof (2 stories, about 24 feet off the ground), it just isn't something that I am going to be installing myself.

So if the best price installed that I can get is $3.40 a watt, well, that explains why there isn't any solar around here. :(

Seriously, in a city of 250,000 people, there are fewer than 200 residential installs of solar. I have never actually seen one in person, only pictures.

So it is possible one of the problems is that there really aren't any serious companies doing the work here.

Even SolarCity won't install here (I called them, they said they won't work in this area due to the co-op not giving big enough rebates).

In my area, the cost of the panels is no longer the primary issue.

I can purchase a 10kw system online including all the panels, cables, inverter, etc. for about $17K.

http://www.wholesalesolar.com/...

That system has 32 panels, the "smart" inverter, racking, disconnect, etc.

The trick is installing it. The lowest total installed price for that system that I've been able to find is $35K. That strikes me as nuts.

I've contacted multiple companies, I've had 2 of them quote me systems after looking at my roof.

Making the panels a bit more efficient won't cut the price by enough to matter until the install cost comes down. Maybe I should start a solar panel install company. :)

Actually, I learned that in a comment here on Slashdot!

Alas, it's just Rolls, no Royce.

Here's an example.

Surrette 24V, 856Ah bank for $2960. That's 20,544 watt-hours, or 10,272 at 50% DoD. That $0.276/effective watt-hour

Compared to 10,000 watt-hours out of Tesla's product, or 9,000 at 90% DoD, for $3500. That's $0.389/effective watt-hour.

The Li-ion is significantly more expensive, but as I said in my first reply, it won't take much more to drive the price of the Li-ion under that of the lead-acid. The price of Li-ion has literally halved over about the last 5 years and Tesla's gigafactory will only help that along.

Lead acid batteries are still about half the price per kWh (look near the bottom, at the 48v x 400Ah bank), and come with the same 10 year warranty. Cars care about weight, houses don't.

The new thing here isn't battery storage of solar power, it's lithium-ion batteries instead of lead acid. The price performance for lithium-ion can't compete with lead acid yet, when weight isn't a factor.

Tesla is selling the complete package with remote monitoring, not just batteries. The price is actually cheaper than some other wholesale solutions

I just did a price check and a 10kwh rolls royce deep cycle system with 4 of those batteries is about 1500 USD. Tesla wants 3000 to 3500. At that price, I could buy 20kwh to 30kwh in conventional lead acid batteries.

The primary advantage of the Lithium batteries is that they're light. But in a static location what is the point of them? Who cares how much the batteries weigh if they never get moved? They sit in a utility closet somewhere in your house and that's it. I'm really confused as to why anyone would pay DOUBLE for Teslas batteries?

Am I missing something? Why would I pay TWICE as much per kilowatt hour?

What is more, deep cycle lead acid batteries can be reconditioned giving them a second life. I don't think you can do that with lithium batteries.

Help me understand. This makes no sense to me.

Here is a link to what I'm looking at as competition:
http://www.wholesalesolar.com/...

How are the tesla batteries better than that for this application?

The Tesla batteries are warranted for 10 years (probably over 3500 cycles). The Lead Acids put a lot of disclaimers about maybe reaching over 1000 cycles. If you take very good care of your lead acids, you'll have to replace them every 3 years or so, so mulitply your costs by 3 before comparing to the Tesla batteries. That's rounding everything in favor of the lead-acids, btw.

Well, admittedly, that's also making some assumptions on the Telsa batteries as well, I guess. All we really know is capacity, warranty length and a proposed use.

I just did a price check and a 10kwh rolls royce deep cycle system with 4 of those batteries is about 1500 USD. Tesla wants 3000 to 3500. At that price, I could buy 20kwh to 30kwh in conventional lead acid batteries.

The primary advantage of the Lithium batteries is that they're light. But in a static location what is the point of them? Who cares how much the batteries weigh if they never get moved? They sit in a utility closet somewhere in your house and that's it. I'm really confused as to why anyone would pay DOUBLE for Teslas batteries?

Am I missing something? Why would I pay TWICE as much per kilowatt hour?

What is more, deep cycle lead acid batteries can be reconditioned giving them a second life. I don't think you can do that with lithium batteries.

Help me understand. This makes no sense to me.

Here is a link to what I'm looking at as competition:
http://www.wholesalesolar.com/...

How are the tesla batteries better than that for this application?

A small lead acid bank capable of driving a house for an evening isn't that expensive.

Please define "not that expensive".

Eight of these for example would run you just about $3000 (I chose 8 to get you to a 48V system, the common configuration for off-grid systems these days). I include shipping but not the wiring and interconnects and such to make them work for you:

http://www.wholesalesolar.com/...

A lead-acid system shouldn't be discharged more than around 20% in order to avoid longer term damage; you can discharge them more deeply but you'll shorten their life significantly:

http://www.solar-electric.com/... of Batteries

Scroll down to the "Cycles vs. Lifespan" section and click on that chart. It's amazing.

So if you are likely to use half of your storage (~225AH for those selected) then a single set of batts would be discharged 50% in normal use. At that rate the batts will last you around 1000 charge/discharge cycles, so a bit less than 3 years if it's every day. If you want them to only be discharged 75% (moves you up the lifetime curve to 2000 charge/discharge cycles or around 5.8 years) it'll cost you double the price above, or around $6K. And quite honestly 225AH is a very shallow system....we're not talking about much being on overnight here. You definitely couldn't consider running a microwave--you'd tap that puppy right out.

I'm leaving out the equipment costs and such; charge controllers to dump power into the batteries and an inverter to take power out will add around $5K more.

I love the idea of as many folks as possible having back up and/or being off-grid entirely (I am) but it ain't cheap. I did it because I had no other choice here; the house is 5 miles away from the nearest power line.

Ferret

Lets take your typical home of 2,000 sq/ft that uses a more modest amount of power, say 1/3 of what I use.

Their average monthly bill is about $100 a month and it'll cost about $30,000 worth of solar panels and batteries to remove it.

I live in a home very close to average (a little smaller in square footage, with insulation that met code about 20 years ago)

I've averaged 740 KWh per month of electricity over the last 12 months, and my average power bill was $105.79. This calculator suggests that I'd need about 5500 watts of capacity to replace 100% of my usage, which would cost less than $10,000 for most of the choices on that page (plus installation). Even if installation doubled the price to $20K, your estimate is still 50% too high.

And that, by the way, is ignoring (a) tax credits (and Georgia's state tax credit is quite good), (b) the fact that I'd insulate some more before buying a solar system, reducing the capacity needed further, (c) the fact that I'd probably DIY most of it, and (d) the fact that electricity prices keep going up over time. Considering those factors, I'd probably spend $7000 or less and break even within 6 years.

In fact, pretty much the only reason I don't already have a solar system is that my roof will need to be replaced relatively soon, and I don't want to have to remove and reinstall the panels when that happens. Actually, looking this stuff up now makes me want to go ahead and replace the roof this year, rather than continuing to wait...

Lets take your typical home of 2,000 sq/ft that uses a more modest amount of power, say 1/3 of what I use.

Their average monthly bill is about $100 a month and it'll cost about $30,000 worth of solar panels and batteries to remove it.

I live in a home very close to average (a little smaller in square footage, with insulation that met code about 20 years ago)

I've averaged 740 KWh per month of electricity over the last 12 months, and my average power bill was $105.79. This calculator suggests that I'd need about 5500 watts of capacity to replace 100% of my usage, which would cost less than $10,000 for most of the choices on that page (plus installation). Even if installation doubled the price to $20K, your estimate is still 50% too high.

And that, by the way, is ignoring (a) tax credits (and Georgia's state tax credit is quite good), (b) the fact that I'd insulate some more before buying a solar system, reducing the capacity needed further, (c) the fact that I'd probably DIY most of it, and (d) the fact that electricity prices keep going up over time. Considering those factors, I'd probably spend $7000 or less and break even within 6 years.

In fact, pretty much the only reason I don't already have a solar system is that my roof will need to be replaced relatively soon, and I don't want to have to remove and reinstall the panels when that happens. Actually, looking this stuff up now makes me want to go ahead and replace the roof this year, rather than continuing to wait...

A standard solar panel (like http://www.wholesalesolar.com/...) is about $150/m^2.

The size of California: 423 000 km^2. One-fifth of 8% of that, to meet the current need, is about 6768 km^2.

At $150/m^2, that would be approximately $1E12. That's [only] $26 000 per citizen. Start the haggle!

You are so very wrong.

Solar IS cost competitive. And with in a very short period, if current manufacturing price drops continue, it will be the cheapest source of power. But sure, ignore the real numbers the real reality of the situation if you wish. These numbers have been the talk of wall street for more than 2 years. Solar companies are turning down investment right now because there is too much being offered. But feel free to continue to display your ignorance. Even a fool could verify the real numbers with Google.

Ok, first, you're a moron.
Yes, if you read some nonsense put out by a "Green energy" group... it's easy to get confused... if you're a moron.

Coal has an average btu of 20,000,000
http://www.eia.gov/tools/faqs/...

It takes 10,107 BTU of coal for a power plant to produce 1 kilowatt of power.
http://www.eia.gov/electricity...

Basic math is 20 million / 10,107 = 1979 killwats per short ton of coal

The price of coal per short ton: $56.30
http://www.eia.gov/coal/news_m...

$56.30 / 1979 = Coal costs 3 cents per kilowatt

If you exclude taxes, regulation and infrastructure.

Now you're going to say "Solar's free!"
No it's not. You need a solar panel. Just like coal needs a mine and equipment.
The average price of a solar panel system for your home is $10,000... I'm even including federal subsidies. The real price is almost double.
http://www.wholesalesolar.com/...
and it lasts about 20yrs.

The average us household uses 11,000 kilowatts per year
http://www.eia.gov/tools/faqs/...
So in 1yr, that's $313 worth of coal.
Over 20yrs, they'll use $6000 worth of coal.

That's production of the energy source, compared.
Solar is almost twice the cost.
The rest of the money you pay for coal power is going to the government, who will still want their money after coal is gone.
We're still need the electrical grid. I doubt the panels will be on your home, they will likely be somewhere else, and there will be batteries.

I'm looking here and I'm looking at my electricity bill that I share with my neighbor, and how many KW hours we use, and I don't see a small cost at all. It looks like a rather big cost would not work for us. Granted, that was a quick web search, but hey, I'm all ears.

Every licensed installer in my state charges 6-10x the wholesale panel price and will only do a fixed bid install that is about 4x the T+M labor cost.

Citation? Which state? My Anecdote: I walked into the solar place in my town and the first thing they proposed when I laid out my situation was that I do the install myself. About the only labor I couldn't do myself would be the final hookup. They'd provide the plans and instructions.

I'm not seeing any requirements to use a licensed installer here. It might be a state/city requirement.

In effect I can put up the 100 or so pannels to meet my current needs for 30k including skilled labor yet the cheapest installer it looking for 100+ with the government programs taking it back down to 80 meaning they are making 70+k on whats quoted as a 2 day job with a 5 man crew.

100 panels? How much electricity do you use? 25 would cover the average household in the USA(10,837 kWh/year, each panel producing 437 kWh/year, even in the middle of the country). Standard panels today are 250-300 watts each. Even the cheapest pallet of 20 300 watt modules will run you $5,270, or $26,350 in panels alone, without racking or inverters(~$4.5k). Checking other online sites shows similar pricing.

As such, wanting it done for $30k means the workers would be doing it for free. The $70k worth of 'labor' does seem inappropriate.

The most interesting part about Germany's Solar deployment is that they have almost no utility scale deployments. Almost every deployed panel is on the roof of a building of a privately owned residence or business.

Probably has to do with the form Germany's subsidies takes.

we'd have more power than we could ever use. Germany is proof of that.

Yeah, like we'd ever use more than 640k of memory... If the power is there we'll use it. To make aluminum, power our new EVs, etc...

Still, we have a pretty good example in Hawaii. Due to most of their electricity being oil generated and predominately sunny(but not too hot) weather relatively close to the equator they've actually managed to get to the point where they could have a day where they bust 100% at this point. It's reached the point that you need permission from the electricity company to get a hookup.

Still, let's do some figuring. Leaving Business and Industrial customers out of it for now.
The average US household uses 10,837 kWh a year, or 903 kWh/month.
A 300 watt solar panel takes up about 21 square feet and costs $263, though final install cost will be $1.50-$2/watt.

Each panel can be expected to produce about 789 kWh/year, ideally placed. Competing against 10 cent electricity, payoff would be about 8 years. Note: I'm using average cases here. I almost bought solar panels for my house, given that I have a nice south-facing roof. On the other hand, I live in Alaska. Even with our relatively expensive electricity I couldn't make it make sense due to substantially LOWER power production than I'm figuring and higher costs(even doing most of the work myself).

Anyways, getting back on topic, that means that each homeowner would need to install 14 panels, on average, to cover their energy needs, assuming they have a retired Model-S battery or something to provide stability.

Some interesting calculations I've made in the past:

1. A retired Tesla Model S battery with 70% capacity remaining repurposed as a giant UPS will provide the average household 2 days worth of electricity
2. The average household would use ~50% more electricity if they replaced their vehicles with EVs(note: 2 days of electricity in an outage from your old battery doesn't include charging your current EV)
3. Start busting 20% of your total energy(and Germany is only at 5%) from solar power and it makes more sense to charge EVs during the day
4. It would take approximately 200 1GW nuclear plants to make the USA carbon neutral for electricity. Again, lots of batteries would be handy...

The factor you should be using rather than 6.8kWh/m2.day can be found here;

http://www.wholesalesolar.com/...

If we have a panel rating of 3.6 kw,

3.6KWp x 6 hrs/day x .95 (loss factor) = 20.5 kwh/day

Notice the units work out.

Huh? The solar panels won't even offset the power demands of the building.

Nonsense.

My house used 975 kilowatt hours last month, about average for me most months. Supplying my house with 100% solar power would take approximately 20 305 watt solar panels with a battery system for night time. 20 panels fits on one pallet for shipping and covers approximately 400 square feet. That's less than half of my south-facing roof space. I could order two pallets today and cover my roof with enough panels to power my entire house twice over.

Or my entire house plus two electric cars from Tesla with enough left over to power an electric lawnmower. For around $12,000.

You don't seem to understand basic economics. Your consumption is reduced when you use energy that is generated. You get paid for energy fed back into the grid when you are not using it.

No, you don't seem to understand basic economics.

I realize that you think vague general ideas trumps actual numbers, but in reality they do not.

In effect, you have made it even harder to recover the costs over 5 years because you used more panels than you needed in order to have that surplus electricity that you think is a magic bullet, so your hand waving about it means absolutely nothing to people with a brain because they know that having a surplus costs fucking money.

Do some math, find a supplier, find an installer, then show us some numbers. if thats too hard for you, then maybe you shouldnt be lecturing anyone about basic economics. Here, i'll start this off for you: The cheapest system that would produce a monthly surplus costs $12,515 from this supplier.. and that doesnt even fucking include installation cost or roof racks. To produce a 100% surplus, that would cost $23,770 but of course only get you back $5583.60 over 5 years and save $5583.60 over 5 years, for a total loss after 5 years of $12,602.80.. again not including the cost of fucking installation.

Don't assume he was going for 100% of household needs. Rarely is the sweet spot on the bell curve of costs/rebates/credits anywhere near 100% (and apple is surely getting incentives to max this out).

He is correct, a 5-year payback is the norm. You size the array to maximize your bang-for-the-buck.

The economics are basic, and they work.

You don't seem to understand basic economics. Your consumption is reduced when you use energy that is generated. You get paid for energy fed back into the grid when you are not using it.

No, you don't seem to understand basic economics.

I realize that you think vague general ideas trumps actual numbers, but in reality they do not.

In effect, you have made it even harder to recover the costs over 5 years because you used more panels than you needed in order to have that surplus electricity that you think is a magic bullet, so your hand waving about it means absolutely nothing to people with a brain because they know that having a surplus costs fucking money.

Do some math, find a supplier, find an installer, then show us some numbers. if thats too hard for you, then maybe you shouldnt be lecturing anyone about basic economics. Here, i'll start this off for you: The cheapest system that would produce a monthly surplus costs $12,515 from this supplier.. and that doesnt even fucking include installation cost or roof racks. To produce a 100% surplus, that would cost $23,770 but of course only get you back $5583.60 over 5 years and save $5583.60 over 5 years, for a total loss after 5 years of $12,602.80.. again not including the cost of fucking installation.

Wind, solar and geothermal can't ramp up fast enough to meet power demand, AFAIK.

When considering total power demand, that is probably wrong (2027 is probably a bit optimistic):
http://en.wikipedia.org/wiki/Growth_of_photovoltaics

Of course, demand response is an issue.
Solving peak demand during the day is easy: have installed capacity equal or surpass peak demand. Turning solar panel power production on and off should be pretty much instant.

Nights are the obvious real (technical) issue for solar. Probably the most viable solution is introducing buffers of batteries, hydrogen or carbohydrates.

Let's look at the matter from a household perspective. According to what I can find, the average US household uses about 15,000 kWh annually. Let's go naive and assume those are evenly spread across the year: 15000/365 =~ 41kWh/day.
Current Lithium-Ion cells are about 250Wh/liter and about 2.5Wh/USD. That means that the volume of cells required to store a day of electricity usage in the average US household is about 41000/250 = 164 liters (dm^3). Stacking these blocks one high, we end up with a volume of roughly 1.3m x 1.3m x 0.1m (which is obviously negligible). The naively calculated cost of such a storage unit would be 16.400 USD.

My calculation seems to be fairly accurate: http://www.wholesalesolar.com/battery-banks.html

Now the above is based on current day technology, supply and demand. I'm pretty sure technological progress will make the above economically even more viable.

The prices of solar cells have been dropping rapidly over the last few years. I think the "green" movement is finally driving up demand to the point where they're becoming commodity items instead of specialty items. They're now available in prices under a dollar per watt, which is about 4 times cheaper than they were just three years ago (the last time I was looking at a rooftop array.) That means today you can buy 400 square feet of solar panels for $5,220, capable of producing a peak power output of 5,500 watts. Not that you'll get that much power with every minute of sunshine, but it could keep a large set of batteries charged.

Of course there's extra money involved - the panels won't mount themselves on your roof, and you'll have to buy an inverter and wire it into your house. Batteries are surprisingly optional, by the way - unless you want to run off the grid, consider selling the electricity back to the electric company instead of storing it yourself. When the smart grid arrives it could make money, as the peak power prices generally coincide with the brightest and hottest days of the year.

I'm not sure how cheap you're expecting them to be get, but they're available today, and a lot cheaper than they were even just a few years ago. The only thing stopping you from buying them is inertia (and the money, of course).

That's right. And the hardware that does that costs about $20,000 - $30,000 to install and certify. It's called "anti-islanding," as I said.

And is required for installing solar panels that are grid-connected.

http://www.wholesalesolar.com/inverters/grid-tie.html
IG-4000 Fronius Inverter 2940002: 4,000 watts / 240 volts Sinewave $2,250
http://www.fronius.com/cps/rde/xchg/SID-168D8631-4108EEFC/fronius_usa/hs.xsl/2714_1477.htm
Anti-islandinig protection: UL 1741, IEEE 1547

You're not saying that hooking up a $2250 piece of equipment costs $17000-27000 to install, are you?

Proof? If you stand outside a solar panel manufacturer in china with your arms out, they will sell you a working 250 watt module for less than $0.80/watt. By the time you get it to the US, you've added $0.40 for shipping/middlemen. Pricing here. We'll round to get to $1.25 a watt for a solar panel. If you do all the work yourself, you'll spend another $1.50/watt buying the hardware needed to mount, install and wire the panels. You'll have to spend another $1 a watt for the permits and a specially certified electrician to do 1 hr of work to connect the last foot of cable. (Rip off alert!) So 40% of the cost of this solar system is caused by regulation that doesn't add much value.

And that's if you do the work yourself so think how much time you've expended in 120-180 days trying to get those permits. Paying someone else to do all the work will take this $3.75/watt installation up to $5.50 to over $7.00 a watt. Getting reasonable permitting and more competition in installation/electricians is what we need to drive the costs down. That means we need the VOLUME of installations to climb to Germany-levels so that we stop letting contractors and towns rip us off and keep us from installing these systems on our homes.

Some calculations to show the impact. A 4 person family home generally would need a 10kw system to cover their whole energy bill (double production when the sun's shining, grid connected at night). We're talking $35k for a DIY system, which could as much as $10k lower if the permitting/contractor racket didn't exist. We're talking $50k-$70k if you let a contractor do the work and laugh all the way to the bank. Most folks only put in a 25-50% system because it's too much capital to expend. $35k for a system at today's mortgage rates put it within 10% of the cost of that grid electricity... with no government subsidies and assuming no increase in grid electricity rates... Add those subsidies and you've got a 3 year NPV.

Full disclosure: I work in the solar power industry building machines that are used at solar panel manufacturers to make cells to be placed into modules.

2 of these http://chetcomarine.com/coleman130wsolarpanel.aspx, 1 of these http://www.wholesalesolar.com/products.folder/wind-folder/airx48marine.html.

Replace my 30 hp Yanmar Diesel with an electric motor. I really only use it for docking and mooring, I'll luff through the doldrums. I worry more about too much wind rather than not enough.

Double my current 6 6v golf cart batteries. and I could circumnavigate in comfort, and use all my gadgets.

and I'd need a new boat, my little Pearson is fun for the coast but I think the ocean would break her

Just saying that we have better ways to perform the task already.

There is one wind turbine from Honeywell that claims to activate at .5mph. It might work for your situation.

Also, since you sound like an enthusiast there are instructables that have projects to use compost to produce methane for cooking/heat/electricity.

You have done a lot of work already, so it might be worth checking into refinancing with a green mortgage/energy efficient mortgage to knock a couple basis points off or to finance additional improvements. Some insurance companies give you a discount on homeowner's insurance if you have a green home, too.

It still takes about 5 years to recoup the cost of a residential solar system-- even with huge government subsidies!

But energy is free after that whereas you have to keep paying for distributed power, even with huge government subsidies to coal, natural gas, and other fossil fuels. Solar panels are warrantied 20, 25, even 30 years. I think the shortest warranty for hardware are on batteries, yet Surrette/Rolls has a 10 year warranty. On the other hand Enersys Batteries only have a 5 year warranty. Even if you have to replace the batteries every 5 years, you still save money.

Some, like you?, complain about subsidies for alternative energy but you say nothing about subsidies for "conventional" energy. Coal? It gets billions of dollars in subsidies, here's, Chevron's CEO agreeing with the Sierra Club to lobby to end coal subsidies. Rep Edward Markey practically brags that My Climate Bill 'Has Huge Subsidies For Clean Coal! Huge!'. He details some of the subsidies nuclear power and other's get. How about this: Global Dirty Energy Subsidies Top $550 Billion Per Year. A blog entry on the Financial Times website says The cost of fossil fuel subsidies: $557bn. How about the US? The Policy Archive says that between 2002 and 2008 "Fossil fuels benefited from approximately $72 billion over the seven-year period, while subsidies for renewable fuels totaled only $29 billion."

If you want to complain about subsidies complain about the subsidies conventional energy, and agricultural businesses, get. A Reason blog entry says Agricultural Subsidies: Corporate Welfare for Farmers.

Falcon

I wanna know too. :-)

The cheapest prices I found so far are these:
http://www.wholesalesolar.com/solar-panels.html

For $200 you don't get much. For $500-600, you get a reasonably decent 200W panel. But you'll probably need more to power an entire house, unless your family is really, really frugal. :-)

I figured out that two 200W panels will most likely fill my personal needs, but they would actually be mounted on a vehicle (a small RV, sorta) rather than powering an entire house. No, it's not an electric car, the power is simply to operate a handful of devices: a 12V portable fridge, various fans (for air circulation), some LEDs, and of course my laptop. This is a 100% off-grid application, so the panels have to supply enough power even in the middle of winter, though arguably the fridge and fans won't need to run as much then.

I'm leery of the idea that this could be done at 'reasonably fixed cost'. The biggest expense here is going to be orbital lifting - which isn't going to get orders of magnitude cheaper anytime soon. Sure, it'll be more or less fixed, but reasonable?

Basically, even if we say that this power source ends up being 100X cheaper, down to $8/watt instead of $800/watt, it's still 2-8X as expensive as other technologies.

Oh, and it's been bugging me - but $1/watt is NOT a good comparison cost for solar power - the figure for the orbital power station is for a station, not a panel.

A better figure for solar is $2-4 per watt, installed in a large plant. After all you can't just toss panels on the ground and expect them to work. You need bases, frames, electrical connections, transformers, and inverters. Likely motors to track the sun(increases in efficiency outweigh the increased install cost). Heck, for the scales we're talking about, you're going to need access roads.

I guess my point is that in a professionally installed system, while panels are going to be a major expense, it's hardly the only one. Heck, here's a 'kit' site. Gridtie systems Picking a large one out(tend to scale well), it's $37,201 for a 7kw array. That's $5.31 per watt for material cost alone. Using the 7kw system as a test model, it's $34k for the solar panels outside the kit, 4k for the inverter. Heck, a quick browsing shows solar panels are still closer to $5/watt than $1/watt, at least at retail. So assuming $5/watt for a plant might not be unreasonable as to the raw cost - with many plants hiding how much it's actually costing by figuring in government subsidies before releasing the cost. IE plant's going to cost $2 mil to build, but the government is subsidizing $1 million of it, so they release that the plant's going to cost $1 mil.

I'll have to agree with 4 though I'm sure they'll build the receiving stations - they're cheap after all. The expensive part is in orbit. Then we use one to microwave Bin Laden when he shows his head above ground.

I never get formatting right. anyway, slashdot ate the expensive big ones link:
http://www.wholesalesolar.com/solar-panels.html

You need to look at an Insolation Map. I'm in Colorado - Zone 3, 5 hours/day averaged over a year. So if you need 4000 hours that comes out to 4000/5/365 = 2.19 years - not bad at all!

Starts looking a little worse once you figure install costs - another $1-1.50/watt, generally speaking

Add another $.50-1/watt for the inverter and miscellaneous, and you're up to $3/watt of capacity.

10k hours, figuring 8 hours a day, 365 days a year would be 3.4 years for raw payback on the panels. If you're not that optimum, it'd stretch to 4-5 easily.

Figure in the cost of the inverter and installation, and it jumps to 12-15 years easily, before any cost of capital expectations.

They not only have to make the solar panels cheaper and better, they also need to work in the install costs and make inverters a lot cheaper. Or start producing DC appliances. Though you should heat water mostly with a solar water heater, much cheaper and more efficient if you only need to heat water, not produce electricity.

Essentially, I use the power utility as my batteries - during sunny days I generate much more electricity than I use and the excess goes into the grid, and then I use power from the grid on rainy winter days and during nighttime.

Have you considered replacing one of your inverters with one from Outback Systems to fee your critical load (bath, hall, bedroom lights, freezer, fridge, computer, & TV?

They have a very nice grid tie system using batteries which is power outage proof.
http://www.wholesalesolar.com/products.folder/inve rter-folder/outbackGVFX3648.html

For a couple grand more, in the case of some good inverters that are designed for it (such as some of the Xantrex models), you can add a box with a relay, a phase-difference monitor, and a subsidiary "brain" board (or get an inverter with the function built in). (Actually the box in question usually also has the line monitoring circuit and combines with inverters that are otherwise stand-alone non-grid-tie.) That box will disconnect the inverter-and-keepalive-lodds from the line and let it keep going during an outage, then tell it to drift phase until it matches and hook it back up once the grid is back and has stabilized.
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Outback systems has this down to an artform in a very robust package.
http://www.wholesalesolar.com/products.folder/inve rter-folder/outbackGVFX3648.html
This one has the advantage of both a battery system which operates at night in an outage, and power company gridtie.

Most gridtie systems do not use batteries. they use the power company as a battery. Batteryless systems are prone to power outages.

You can get them significantly cheaper and higher power than that, but that's within the ballpark, yeah. See Wholesale solar for some prices and brands. (I have never dealt with them, just found them through Google)

What he should be doing is marketing this to rural farmers in developed countries. If I lived on a farm with access to the fuel, I would love to have a kilowatt generator for $1000 to supplement my electricity use.

A kilowatt generator for a $1000 isn't a great deal, you can get those for $150. You could even get a 1000 watt wind turbine for $2,115
and you wouldn't need fuel.

Actually, if a place had steady wind, then I'd say forget about the power generator part and you'll save yourself a lot of trouble with a wind turbine or two.

That brings up a point though, when you are talking about new infrastructure you should make sure that the local people themselves can afford its upkeep otherwise you will be making them dependent on political handouts forever.