Google's Project Sunroof Tells You How Well Solar Would Work On Your Roof 105
An anonymous reader writes: Google's Project Sunroof aims to make the task of installing solar panels easier by providing financial advice and stats on what solar energy could do for you. The project is only available in San Francisco, Boston, and Fresno for now. Techcrunch reports: "To get started, you simply plug in your address and some data about your monthly electricity bill, and the tool will tell you what the recommended solar installation size is and how much it would cost to buy or lease the hardware. In case you want to go ahead with a solar install, the tool also lets you reach out to local solar providers. Google says these listings are sponsored, so chances are it'll get a bit of a kickback when it generates a sales lead for these companies."
Not available yet... (Score:5, Insightful)
Darn it: "Sorry, Project Sunroof hasn't reached this address yet."
Can't say much about it then.
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The project is only available in San Francisco, Boston, and Fresno for now.
Granted, I think our dear slashdot editors could have been a little more explicit with that constraint but it is there...
Re:Not available yet... (Score:5, Informative)
http://pvwatts.nrel.gov/ [nrel.gov]
Hot cool tool (Score:2)
Hot. We're looking at putting in a 20MegaWatt solar array on our farm. This would be a cool tool.
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Just checking you didn't accidentally use the wrong units (KW maybe?)
If you are installing 20MW then you are definitely up to the scale of a reasonably serious commercial venture. I would imagine with the money needed for that kind of investment, you would've already paid a consultant to work out the financial feasibility and the optimal installation location.
This tool is for residential rooftop solar which is hobby scale compared to yours.
20MW vs 20kW (Score:2)
It's still a pretty serious system if he's looking at 20kW. For my house I'd be looking at a 4-6 kW solution, covering the entire south facing side of my roof, and my roof is about as ideal for solar as it gets, shape wise.
20kW would require a much larger house, and probably a barn or two as well.
Strange limitations (Score:5, Insightful)
Google says these listings are sponsored, so chances are it'll get a bit of a kickback when it generates a sales lead for these companies.
Oh, riiight! "We don't have any partners outside those cities yet, so the rest of you can go fuck yourselves". Got it.
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Local, state and federal subsides vary drastically only a few miles apart. That database would tax googles servers.
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Not google's servers, google's interns who have to put in/clean/standardize all that data.
Re:Strange limitations (Score:4, Insightful)
Local, state and federal subsides vary drastically only a few miles apart. That database would tax googles servers.
That's right. The subsidies are required to make this look good. It is, after all, sponsored by installers. The calculator naturally assumes everything is optimum, and doesn't get very detailed when it comes to additional expenses that may be incurred during installation. It also assumes 2.2% per year rate increases, which is not necessarily going to happen.
I did a spot check on their Redwood Ca numbers. They calculate using solar insolation equivalent to 5 hrs/day, but real numbers are about 4.7 hrs/day.
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Re:Strange limitations (Score:5, Insightful)
If you aren't willing to pay for alternative energy, then don't be surprised when you don't get it. Google helps advance that cause and all you can do is complain that they are a business.
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Shade, local terrain, building codes, subsidies, power company buyback policies and rates. There are also a lot of odd business arrangements that are localized that can dramatically reduce the solar capital cost.
I have no idea if they account for any of these factors, but there are certainly a lot more factors than weather-adjusted annual insolation.
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Annual insolation, even after considering weather, counts as a well-documented stat across the entire US. Why would they limit this to just a few key cities? .
I think it's because they do additional processing to take into account shadows and roof slopes to better estimate the viability of solar on a building. It pretty accurately shows the that north half of my roof is in shadow, and it captures the shadow from the large building to my south that hits part of my roof.
No kidding (Score:2)
I live in Arizona, which is one of the very best places to do solar since it is very sunny, very hot, and a significant portion of your electrical use is for cooling so the panels generate the most when you need it the most AND shade your roof. However they aren't available in this area. Really? I'd the the desert of the southwest would be the first place since, well, that is THE place for solar. I mean ya solar can be used and have some benefit anywhere in the world but the hot, sunny, dry places are where
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I live in Arizona, which is one of the very best places to do solar since it is very sunny, very hot, and a significant portion of your electrical use is for cooling so the panels generate the most when you need it the most AND shade your roof. However they aren't available in this area. Really? I'd the the desert of the southwest would be the first place since, well, that is THE place for solar. I mean ya solar can be used and have some benefit anywhere in the world but the hot, sunny, dry places are where it really works well.
What do you pay for power?
It appears that what Google did is pick two high cost cities to make the project look good at launch. San Fran probably has higher than average electric rates, I would imagine that Arizona has lower than average rates.
How many homes around you have solar on them?
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We don't pay a whole lot, we have multiple generation stations, and sell power to California. Also cost of living is generally fairly low in Arizona.
Solar is becoming fairly popular. Most new houses have it, and many businesses do. Older houses are not as often retrofitted though, due to cost.
I live in a condo, so I can't just have it installed, it would have to be a thing the association does.
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Because Google owes us, big time.
Re:Strange limitations (Score:4, Informative)
Annual insolation, even after considering weather, counts as a well-documented stat across the entire US. Why would they limit this to just a few key cities?
Because this provides dramatically more detail than regional average insolation. It tells you how much insolation each portion of your roof receives, accounting for local geography, flora and other buildings. That takes some moderately-detailed 3D models and heavy number crunching. The 3D models come from Google's project to build 3D models of all population centers using low-flying aircraft with angled cameras, so Sunroof will only be available in regions where the models are available (zoom in in Google Maps in your area to see if it's already 3D-ifiied) and even then it will take time to crunch all the data.
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Oh, riiight! "We don't have any partners outside those cities yet, so the rest of you can go fuck yourselves". Got it.
I realize that fucking yourself is one of the primary activities the Internet is used for, but you also have the option of investigating your home's solar situation using other tools, such as, say, Google's search engine. Assuming even minimal competence, you really don't need to have your hand held every step of the way.
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> Solar Suitability (including insolation, weather and cloud cover) nationwide is well-documented at a very course level.
When considering roof top suitability you need 1-meter resolution or better (each pixel in the output raster images represents one meter squared).
I helped work on a similar project for Minnesota (http://solar.maps.umn.edu/app/).
Might as well ... (Score:5, Informative)
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... just contact a local system installer. The insolation data for a particular region is already known and publicly available. What will affect your particular system are things like local shading, roof pitch and orientation and cost of installation as affected by your house and lot particulars. Local installers will also be familiar with your utilities solar programs.
I have, the payback period is currently running more than a decade... If you play with the numbers and depending on your assumptions, they were able to get the numbers down to 7 years payback, but there are a lot of "what-ifs" put in there, all in favor of solar.
Put the numbers against it and the number approaches 20 years. The average was 12 years, but even then it could go either way.
That is, frankly, not a good investment, which is why no one around here is installing solar. I imagine in places with
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Yeah, but the most important number is the cost of electricity, which is _assumed_ to hold constant, rather than go up in price. Given the shit to natural gas which is historically cheap right now, and the difficulty of going back to coal for baseload, that's not a very good assumption on balance.
We opted not to get solar, but we live in San Francisco. Our home doesn't even have an A/C, just an old furnace. The one thing that almost persuaded us was that if we got solar this year we'd be locked into a favor
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Yeah, but the most important number is the cost of electricity, which is _assumed_ to hold constant, rather than go up in price.
That is a fair point, and it is how you get my numbers down to just 7 years... by assuming that massive price increases are around the corner.
They might be, my crystal ball isn't working, so I really don't know.
The biggest challenge is that the cost to install a system large enough to make it worth doing is equal to a really nice car. I'd need a 10 kilowatt system just to replace maybe 1/3 of my energy use.
Of course this past month has been pretty high, with the AC running all the time, but we used 4,189 k
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I was feeling really bad about the 780kW-hr or so we used at my house last month, but now I don't feel bad about that at all. Anything over about 20kW-hr/day makes me think we need to conserve more*. But an average of well over 100kW-hr/day? Wow.
*I'm always running around the house turning off lights in rooms that are unoccupied, ceiling fans running when nobody's home, stuff like that.
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*I'm always running around the house turning off lights in rooms that are unoccupied, ceiling fans running when nobody's home, stuff like that.
:) Ceiling fans probably could use a nice boost to energy efficency, but as for the lights, go with LEDs. The cost and quality have finally reached the point where they make total sense, the payback is a year, 2-3 for rarely used lights, less for often used lights.
My kids often leave the bathroom light on at night, 4 of those round clear 40 watt bulbs. I replaced them this summer with 5 watt LEDs, more light than the old clear bulbs and a whole lot less power. Now instead of 160 watts (and heat that has
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I'd say insulation is your best bang for the buck. Rather than replacing windows (yes, very expensive) you should consider just putting in heavy curtains or blinds; the air barrier they provide can be quite effective. Yes, this affects lighting, but if you do it selectively, such as in rooms that aren't often occupied, you can get a big impact for little cost. Even closing AC registers in little-used rooms helps.
We are in the process of switching to LEDs, but generally we do it when an existing bulb burn
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What will affect your particular system are things like local shading, roof pitch and orientation
This is the data that Project Sunroof attempts to estimate, based on Google Maps' 3D models of buildings, nearby trees, etc. Getting a local installer out to look at your house will (probably) give you a better estimate, but it's a lot more effort than going to a web site.
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Yep. I did my own calculations and got 850kWh/month or about 10,000 kWh/year. I used satellite data and got 951kWh/month or 11,400kWh/year. I used the State's PVWatts program (which for an array less than 10kW, the state uses to confer solar energy credits without measuring generation) and got 9280kWh at an azimuth of 165 and a fixed angle of 54 from vertical, 9820kWh at an ideal azimuth of 180. The PVWatts calculation assumes 9% loss in system; the default is 14%, but I target a micro-inverter system
This already Exists (Score:1, Informative)
There is already a the PVWatts calculator at on NREL's website. You input your location, the type and placement of the solar panels and it tells you how much power to expect based on local weather measurements. Since these are the people gathering the data, I can't imagine google's project does anything than access this same database.
http://pvwatts.nrel.gov/
Re:This already Exists (Score:4, Informative)
There is already a the PVWatts calculator at on NREL's website. You input your location, the type and placement of the solar panels and it tells you how much power to expect based on local weather measurements. Since these are the people gathering the data, I can't imagine google's project does anything than access this same database.
http://pvwatts.nrel.gov/
The NREL site just looks at location and weather to estimate solar availability -- The Google site attempts to calculate usable roof area and take into account shading from nearby trees and other structures.
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Once you factor in things like government subsidies, solar make economic sense for almost everybody, no matter how small your budget. A 20 year pay off is still a 20 year pay off, period.
You have an interesting view of economics.
A 20 year payback might as well be forever... The same money could be better spent in many other things. The money isn't either spent on solar, or nothing...
For example, we replaced our 11 year old 13 SEER HVAC with a 16 SEER dual speed, dual stage unit. It was $18K including some ductwork for a pair of TRANE units, a 5 ton and a 3 ton. The payback period is 10 years on that, less if the cost of power goes up. My electric bill 2 years ago in August was $700, th
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Once you factor in things like government subsidies, solar make economic sense for almost everybody, no matter how small your budget. A 20 year pay off is still a 20 year pay off, period.
You have an interesting view of economics.
My electric bill 2 years ago in August was $700, this year it was $500.
As do you if you think your electric bill 2 years ago demonstrates anything.
My electric bill 2 years ago in August was $70, this year it was $50 and I didn't even replace an air conditioner, so clearly you could have gotten the same payback by doing nothing.
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Of course efficiency is always the best option if there is low hanging fruit.
That is why I went ahead and replaced the HVAC system rather than repair it. I figured the system would end up needing another expensive repair in the next 10 years, making my true upgrade cost half of what it really was, 2 expensive repairs during that time (it was already 11 years old).
Looked at that way, the payback period is really 5 years, or perhaps 7.5...
Another consideration is the old system had a hard time cooling the upstairs during hot summer days, even running all the time, the new system does
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There is already a the PVWatts calculator at on NREL's website. You input your location, the type and placement of the solar panels and it tells you how much power to expect based on local weather measurements. Since these are the people gathering the data, I can't imagine google's project does anything than access this same database.
http://pvwatts.nrel.gov/
This is the smart way to start, as it has just plain data. The Google project does not rely on this raw data, it appears to be adjusted by the sponsors and have added data. Google and the sponsors are in no hurry to show the data for places where there is no forced buy-back at retail rates, for instance, because that drastically changes the picture.
Like those helpful guys at Home Depot (Score:2)
Lemme alone, fools. I will burn hydrocarbons till the day I die. (just joking here)
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Of course, power generation never changes. Nosiree. Solar PV has never grown either. And nuclear has been with us ever since Edison.
Or you're a dumbass.
Real numbers (Score:5, Interesting)
It will cost, give or take, about $40K to install a 10 kilowatt system on my home.
Returning the 30% federal tax credit back to me puts me at a cost of $28K.
Based on my location in Texas and my current utility rate (total cost) and that I have net-metering, I'll save about $1,400 a year in electricity with such a system.
That puts me at an even 20 year payback period. Now, in fairness, electric rates are not likely to stay the same, adding solar does add something to my home's value, so there is that.
Lets say that electric rates will rise with the rate of inflation, which the government currently says is nearly zero, but will probably rise, then add something to the value of my home, and you get about a 12 year payback period, if you use numbers that favor solar and 17 years if you don't.
What those numbers DON'T take into account is the loss of net-metering, which is a real risk. If too many people go to solar, it will have to go away. If everyone installed solar on their roof and ended up with no electric bill, the power companies would go out of business. Clearly they would actually go out of business long before then, maybe at 20%. You can talk about batteries all you want, but the reality is they likely will get lawmakers to remove net-metering before then.
Regardless, it is a terrible investment, it makes no sense whatsoever from a financial point of view, at least for me. If you pay more than I do for power, then it might make sense for you. I have family in Australia who recently installed solar because they pay more than 25 cents per kWh, so the numbers are quite different there.
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Depends on where you are. Here in Oregon, there are additional subsidies - both state and non-governmental. With these subsidies, my break even point is between 6 and 7 years, so it is a much less risky proposition.
Fair enough... of course, that doesn't mean there is a future in solar being 20% of our nations power any time soon, unless a major breakthrough in cost arrives.
But there is the thing... it already HAS arrived... the cost of the panels isn't that expensive, it is the labor to mount them to your roof, tie them into the grid and your house, add all the other items that are needed.
The panels are what, $1 a watt, give or take? The labor and inverter and other costs are $3 a watt, give or take.
The panels cou
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that doesn't mean there is a future in solar being 20% of our nations power any time soon, unless a major breakthrough in cost arrives.
Why would you require "a major breakthrough" when the cost decreases by several percent every year? Or, to put it differently, you've been living in a continuous breakthough that has been happening over the past forty years.
The panels are what, $1 a watt, give or take? The labor and inverter and other costs are $3 a watt, give or take. This might never make sense, due to the labor issue...
I could have a complete PV system installed for half of the "labor and inverter and other costs" alone. The US is apparently the only major country in the world with this "labor issue". Now you could either solve this problem of yours, or, in the decades to come, watch other countries en
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Why would you require "a major breakthrough" when the cost decreases by several percent every year? Or, to put it differently, you've been living in a continuous breakthough that has been happening over the past forty years.
The panels could become free tomorrow, it would only cut the cost to install them by 25% or so...
The cost is in the labor, not the panels...
I could have a complete PV system installed for half of the "labor and inverter and other costs" alone. The US is apparently the only major country in the world with this "labor issue".
Maybe so, the cost to install a home system here is about $4 a watt, all up. I have no idea how that compares to other countries...
Most of the US also has really cheap power, making it hard to make any sense out of it. My home pays about 11 cents per kWh, my office pays even less, under 7 cents per kWh.
I totally get that in places that charge 25+ cents per kWh, solar
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What those numbers DON'T take into account is the loss of net-metering, which is a real risk. If too many people go to solar, it will have to go away. If everyone installed solar on their roof and ended up with no electric bill, the power companies would go out of business.
The tax subsidies will also go away long before mass adoption. The governments can't afford giving that much money away. Eventually, people will have to pay their own power bills. To be sustainable, selling to the grid makes more sense done at wholesale rates, not at retail rates.
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To be sustainable, selling to the grid makes more sense done at wholesale rates, not at retail rates.
I totally agree, but then the numbers for solar REALLY don't make any sense... The payback varies between 12 years and 17 years for me, depending on the assumptions, and that is WITH net-metering. Remove it and the payback period likely exceeds the useful life of the system.
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Value should be given to the reduction in transmission and distribution costs as well. On my bill the sum of those two items is about the same as the rate for the generation cost.
Hell, there's a charge on my bill to pay off bonds that the California government used to buy power at exorbitant, extortionate rates more than a decade ago during the "energy crisis" created with the "help" of Enron. - that's an extra half cent per kwh that we'll have to pay for freaking ever because politicians got bought out by
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Plus, there's about 8c/kwh that I'm paying for "Conservation Incentives" and another 1c/kwh for "Electric Public Purpose Programs." If all I had to do was pay for fscking power, my bill would be a factor of three smaller. Just saying....
That is insane, my total power cost for my office is less than your "Conservation Incentives" charge.
Wholesale power costs about 3 cents per kWh, give or take a bit. Transmission costs vary, but shouldn't do much more than double that. Then add something for profit and admin overhead.
Anything over 10 cents per kWh has something really wrong with it.
Hell, there's a charge on my bill to pay off bonds that the California government used to buy power at exorbitant, extortionate rates more than a decade ago during the "energy crisis" created with the "help" of Enron. - that's an extra half cent per kwh that we'll have to pay for freaking ever because politicians got bought out by corporations' "free market" bullshit and overpaid for power for less than a year.
In fairness, the people in California keep electing those same politicians, so I'm not sure what to say, other than move somewhere else. :)
I lived in Californi
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You _just_ explained how it was a rational investment.
I did? Hmm, I seem to recall doing just the opposite...
A payback period of between 12 and 17 years is horrible!
It isn't remotely a rational investment.
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I'll save about $1,400 a year in electricity with such a system.
That puts me at an even 20 year payback period.
You're payback is much longer than that unless you have the $28K stuffed in a mattress. Put your money in a mutual fund and the payback is never, even with the subsidies. Same thing if you have to borrow the $28K (unless you can find someone to loan you the money interest free).
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No, I am not payback. Are you payback?
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You're payback is much longer than that unless you have the $28K stuffed in a mattress.
True, but I can borrow the money at 3.5% on my house on a fixed term, so while that isn't free, it is really cheap.
Put your money in a mutual fund and the payback is never, even with the subsidies.
And there is the other side of the coin, what else could you use that same $28K for.
Keep in mind, it really isn't $28K, it is $40K with all of you nice people chipping in $12K to help out.
It really, really, really makes no sense.
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Why is it so expensive? Up here in Ontario I can get a 10 kilowatt system installed for $32k + tax. There's no government rebates but if you set up with the microFIT program you can get the tax back and it pays you around $0.35 kWh (or $0.38) guaranteed for 20 years. The installation price includes everything: panels, permits, inverter, labour, extra meter, etc.
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Why is it so expensive? Up here in Ontario I can get a 10 kilowatt system installed for $32k + tax.
You're saying it as if $32k + tax were cheap. It isn't. For that kind of money, you could have a 30 kilowatt system in some places. I guess the FIT is the saving grace here.
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You're saying it as if $32k + tax were cheap. It isn't. For that kind of money, you could have a 30 kilowatt system in some places.
No, it isn't cheap... He says $32K, my quoted cost was about $40K, both prices are too high.
If I could have a 30 kilowatt system installed for $32K, I would do it. That is close to $1 a watt, at that price, it makes sense, even with our lower power prices...
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I didn't say that $32k was cheap but it's a lot less than $40k especially when you consider when the $32k is Canadian which is approximately $24.5k US today.
So I was wondering where the difference was coming from. Does the US have a big import duty on the panels? Or is Texas not friendly towards solar and have a lot of red tape and fees to try and stop it? Are there not a lot of installers there which is driving up the price?
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Why is it so expensive? Up here in Ontario I can get a 10 kilowatt system installed for $32k + tax.
Good question, that is what the companies in Texas are charging.
$40K for a 10 kilowatt system.
BTW, if anyone is in Texas and knows of a better deal, speak up. If the cost were in the 25K range and it was a real company doing it (not a guy and a truck), I'd give it another look.
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Sunroof doesn't operate in Texas, and perhaps because it's not worth it due to the structure of electricity rates. In California, we've got tiered rates that punish high usage - buying your electricity in Costco-sized bundles costs more than buying it in convenience-store tiny bundles. The statewide solar initiatives (CSI) is done, kaput, played out, but used to pay as much at $2.50/installed-watt or 39c/kwh - but it ended at 20c/installed-watt or 2.5c/kwh. The 30% federal tax credit's the sole big remainin
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"Actually, yes." [Don't sue me, Bro!] http://www.illumitex.com/canna... [illumitex.com]
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Here in the Bay Area, one of the few regions where Sunroof actually is operating, residential electric rates start at 16c/kwh (Tier 1), but rise to 19c, 28c, and 34c (Tier 4) as your usage increases over "baseline". If you size your system to knock out Tier 3 & 4 usage via net metering, the payout's much quicker.
Holy crap that is insane... reminds me of why I don't live in California...
Around here, 7 cents per kWh is a reasonable cost, it goes as high as 10 cents per kWh depending on what plan, how much you use, or if you're in a co-op, etc...
If you combine net metering with time-of-use metering, the payout time can be even sooner, as the Weekday (Monday-Friday), "summer" (May-October), Tier 4 rate reaches 49c/kwh at times of high demand and 38c/kwh at medium demand. The high demand period runs 1pm-to-7pm, and medium-demand runs 10am-to-1pm and 7pm-to-9pm, so the sweet-spot daylight times for solar are generally net-metered at medium-demand and high-demand rates. Notably, this means that west-facing solar panels get a sweeter payback than either east-facing or south-facing on a typically-sloped roof.
Fair enough, so solar makes sense there only because of the completely nuts system of power rates that California has.
In other words, solar doesn't make sense on its own, but it does if you mess around with the market enough to make it work.
The wholesale cost of power in Texa
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Economies of scale: Per kw, whatever ROI you can achieve, it's safe to assume the local power company can generate a lot more energy to both resell and profit cheaper than what you can. That, and you don't have to worry about the 20 year lifespan of equipment, maintenance, and payback. If solar technology is really being mass-produce on the cheap, I'd expect a wider adoption of utility provided solar vs the home owner taking on this investment.
I agree with you... And if it makes economic sense to do it, then by all means, I fully support it...
There is something to consider... the power transmission cost is worth considering...
My home is in a co-op, so I get no choice of power there, but my business is not, it is part of the Texas-New Mexico Power Delivery Company, which runs the power lines you see on the streets. It doesn't sell power, it sells transmission line access.
The actual cost of power that I pay is between 3 and 4 cents per kWh, the
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How did you get 40k? A 10kW system costs about 16k in parts (http://www.wholesalesolar.com/grid-tie-packages). Are you seriously saying installation is another 24k?
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How did you get 40k? A 10kW system costs about 16k in parts (http://www.wholesalesolar.com/grid-tie-packages). Are you seriously saying installation is another 24k?
I have had it quoted... After that I called another company and they were about the same price...
Perhaps there is a business opportunity here if those costs are unreasonable, but that is what the local market is charging...
Of course this also probably explains why no one around here has solar, to the point where I've never seen a house in person with solar on it.
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Fresno?! No one goes to Fresno anymore!
NREL tool is a good alternative (Score:2)
I used the National Renewable Energy Laboratory's [nrel.gov] System Advisor Model (SAM) tool when I designed my 16kWdc rooftop array. You can download SAM [nrel.gov] from the NREL site. They also have a web-based tool called PVWatts [nrel.gov] that is far less detailed, but is definitely easy to use and produces a very reliable estimate if you are thinking about a PV array.
For what it is worth, rooftop solar is facing stiff opposition from utility companies and energy producers because it directly affects their bottom line. Changes in
404. That’s an error. (Score:2)
Not enough data (Score:3)
The only way that this would be accurate is if it looked at the satellite imagery throughout the day and all year long because shadows.
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You're not being very imaginative. They don't need to take pictures every few minutes all year to find shadows; they just need a 3D model. The sun's position in the sky is easily calculated for any given day of the year and time. And they have 3D data (probably collected by airplane) for many areas, as seen in Google Earth or Satellite View on Maps. The data's not perfect (if you've looked at the 3D trees, they're pretty ugly!), but it's a pretty decent tool given that nobody needs to climb on your roof to
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One word: trees. Plus, the only thing you're going to get from GIS is a building foot print. There's no data on the slope of the roof. You need to stop thinking urban because contrary to popular belief, most people don't live in an urban area. I can show you two different Google satellite images of my house, one taken in June and one taken in January. The shadows case by the trees are dramatically different. My point is that you can't get an accurate assessment of available sunlight throughout the day
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But that was exactly my point; Google knows about trees, and they have 3D models of them. Not everywhere in the world, but at least in the areas that Sunroof is covering now (and many others - like I just checked my parents' house in Wisconsin). As to your "most people don't live in urban areas" comment, the US Census Bureau would say otherwise [census.gov]. According to them, it's about an 80%/20% split between urban and rural.
As far as SolarCity, they put exactly what they can charge you in their contract. If someone
how is project sunroof different from sunrun ? (Score:1)
Luxembourg City (Score:2)
Interesting. Here in Luxembourg city (over in ol' Europe), the land register actually also has data on the constructions, and has now for a short while added a feature on their online maps displaying whether it would be worthwhile to install PV on the rooftops - they go as far as displaying which parts of the roof would be of most interest in that context. Of course, they can only give general guidelines, to be confirmed by an expert.
With my own house being at the north end of a row, only my back/front roof
WTF?! (Score:2)
Re: (Score:1)
There are technical and business reasons, but they will get sorted out in the future. Just...not yet. Which is another reason that solar doesn't make so much sense right now. And remember that R&D in efficiency and cost is still ongoing, and the system you buy now will have to keep working for many years to pay you back, while your neighbors' systems that they buy in the future will pay back a lot faster because they're cheaper.