Solar power

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dcooper

Senior Member
I live in the north east. I had one of my contractors ask me about solar panels. He wants to market them and I will take care of the install. He does alot of high end homes so the costomers are there. I looked into it and it doesn't seem cost effective right now.It is the future... but I had a cost of $10,000 per KW. And I live in the Boston area, it's not that sunny all year round. Maybe I was miss informed can I get some feed back? Is this something I should educate myself on?
 

76nemo

Senior Member
Depends.....

Depends.....

I am way up north and solar is booming for the wealthier. A guy from camp had his small home done for a little over $60K. Nice work and done in a weekend. Depends on what you are bidding off of? He gets a check back from the grid as he doesn't frequent the camp all that much. Wood stove heat, no washer and dryer, he does well. I expect the service to pay for itself after awhile.

Sooooo, how do you plan on bidding the jobs?
 

gndrod

Senior Member
Solar

Solar

The cost non-effective part is not a problem when high-end projects are for an energy conscious client. States such as CA, WA, OR, NY, FL, are all involved with payback incentives that help lower grid usage. The Feds are not budging on renewable energy cost tax breaks so that leaves the private manufacturing sector on their own. The solar industry is booming in countries that have overtaken the US(#4 in world production) in both manufacturing and installation of commercial and home installation.

So the answer is 'yes' solar is here depending in what country, and depending on whether applications are associated with commercial or residential. In some States(ie.CA, NY, WA and others), certification to install solar equipment is necessary for qualification of energy usage 'solar rebates' from utility providers. Some NJATC's have certification programs, and there are Independent Tech schools starting to get on board also.

The above data is just a brief idea of what is happening in the solar industry where progress is being made. A good website to follow is www.renewableenergyaccess.com that lists solar industry breakthrough technology and high-end job opportunities coming available. rbj
 
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rexowner

Senior Member
A current benchmark for PV solar is about $8/watt installed.
Can easily go lower for larger, e.g. commercial installs,
and $10 is not unusual for residential -- it's certainly not
a lowball number, but not unprecedented. In California,
a well designed, well installed (e.g. no shade) PV system
might get 1,400 kWH / Kilowatt peak capacity - that
is for an very good install, and most are lower for a number
of reasons.

From glancing at some solar tables, it appears Boston
gets about 84% of the annual sunlight we do. A guess
of 1,000 kWH/Watt would be a ballpark number if you
want to do the math to see the return on investment.

The above is not complete. A few things which might
make the math work out better are:
- Time of Use: the utility may pay more for electricity
in the midafternoon - in our area this may mean ~30cents/kWH
vs 10 cents.
- Variable rate scale: in our area we pay about 10cents up
to a certain point, and then significanly more for more
power usage -- the aim of many PV systems is to shave off
the expensive part of the power usage to make the ROI
better
- Government/Utility incentive/rebates sometimes pay
a significant share of the cost.
At this point the government policy is typically what
makes or breaks the economics for most utility-attached
systems. If you are really interested, places like
Solar Energy International (e.g. I am referencing their
book "Photovoltaics: Design and Installation Manual"
for the Boston vs. California sunlight numbers)
offer education. In our area, the utility, PG&E
offers some good education.
 
L

Lxnxjxhx

Guest
Strong sunlight puts out 60 watts/sq. ft. but you don't get to use very much of this available power.
 

winnie

Senior Member
Just some musing about units (dollars, cents, watts, KWH) based upon what rexowner posted. It's been a while since I looked at this, so I don't really know any of the currents costs or governmental issues.

There are 8766 hours in a year. A generating plant with 1 KWH capacity operating continuously can thus produce 8766 KWH per year.

So when we hear '1400 KWH per KW capacity', this tells us that the solar panel is only being used at the equivalent of an average of 16% (it is actually being used a larger fraction of the time, but not at full power).

He also tells us $8 per _watt_ of installed capacity. This means $8000 per kilowatt of installed capacity.

You can ask the question: how much does that $8000 cost? The simple answer is $8000, but we can ask what an $8000 lump sum is equal to as payments made over the course of time. Think about it this way: if you _borrowed_ $8000, how much would you have to pay yearly. Or if you had $8000 to invest, how much would it pay off each year. I'm not good at figuring the 'cost of money', but take as a rough estimate 5-10% per year. So that $8000 costs perhaps $400 per year.

For that $400, you get 1000-1400 KWH. Mighty expensive electricity in most circumstances.

IMHO that money is far better spent on efficiency measures that mean less energy gets used to provide the same comfort and utility.

-Jon
 

dereckbc

Moderator
Staff member
dcooper, you need to be real careful where you get information. In the last 5-years I have done several stad-alone projects for cell towers where POCO power is not available. Most of what the promoters tell you is rubbish. One of the biggest lies is how much power a system will generate in a given day.

You have to design for Worst Case scenerio which happens to be winter. Without boring you with a lot of math here are two good examples of the same system. One installed in Inyoken CA, and another in Boston MA.

The system is real simple a grid tied system consisting of 1KW array and a 1 KW inverter . Cost is the same approx $10K. The following takes into account ineffieciency of the system

The system in Inyoken CA will produce an average of 5.1 KWh per day on average year round, while the same system in Boston will only produce 2.56 KWh per day.

With those numbers you can do some real quick math to form an oppinion in terms of cost and ROI. Like $10K investment and a POCO rate of 10-cents per KWH. In Boston the payback will not be realized by your grandchildren, In Ca your grandchildren may see the payoff if the house doesn't fall down first.

The problem is Solar Insolation or more simply said Solar Hour Day
 
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gndrod

Senior Member
link caput

link caput

ghostbuster,

The link you gave is like an apparition. Maybe there is something I did not see. Could you fix? rbj
 

SegDog

Member
Solar/PV

Solar/PV

Good questions dcooper...

1. a lot of people think solar hot-water when you say solar. When talking solar-electric, I learned to say PV. Tough, at first, but it's like electrician-talk.

2. on this subject, solar hot-water (DHW and space heating) is extremely efficient and should be discussed by your contractor as part of a package.

3. PV is expensive and difficult to sell until you have a power-outage, then you're the smartest guy on the block. I opted for batteries and inverters as my first step when I started. I was, always, jealous of my neighbor with the big, smelly, noisy generator. The big push is for utility-intertie systems. That's where the rebates are/were. My goal is to get away from the POCO as much as possible; so a hybrid system is worth looking at.

4. There are many websites and the Northeast Sustainable Energy Association has a good magazine with contractor information. A "home power" magazine will answer some questions and create more.

enough for now...


SegDog
 

ghostbuster

Senior Member
gndrod said:
ghostbuster,

The link you gave is like an apparition. Maybe there is something I did not see. Could you fix? rbj
This link in the post works(I just tried it),however it is sometimes flaky.

Try this link and click on the first related link at the bottom of the page.It is really intersting looking at real live data without having to calculate what the calculated sun impact is at a certain latitude.

http://www.powerauthority.on.ca/Page.asp?PageID=122&ContentID=4043&SiteNodeID=252&BL_ExpandID=

Enjoy
 

mfpetryk

Member
We have had a few higher-end residential projects that used photovoltaics. NY has some very generous rebate programs to help cut the costs.
The last project came in at around $60k cost to the owner for a 10kW system.
 

mivey

Senior Member
Solar can be an alternative source but not as reliable as most. For example, I would think of geothermal to be more useful, or landfill gas generators.

Also, another thing to consider. If your average power bill is 10 cents, the value of the energy from solar is not 10 cents. If it is a cloudy or rainy day, where will you get electricity? There has to be a generator, transmission line, substations, distribution systems, conversion & protection systems, service people, etc all allocated to still serve you on a rainy day. The actual value of the energy piece is only a part of the 10 cents you pay on average. The top of stack embedded energy may only cost 3 or 4 cents for coal or even a penny or less for nuke.

In Georgia, market energy used to be in the 3 cent range, now it is in the 5 and 6 cent range. If the poco is in the market, they may can avoid some of this 5 and 6 cent energy. The problem is, the solar energy is not a very reliable source so the value is actually less than market. You can buy guarantees with the market energy.

If the poco is facing a market spike of 50 cents/kWh or even $50/kWh. They are going to cut a deal with a reliable source to avoid paying this high price. I don't see how solar can't provide this kind of value, unless it has some way to store the energy. If you can store it, then you can also provide some demand value.
 
L

Lxnxjxhx

Guest
energy storage

energy storage

Batteries don't give back all that you put in them, and they have a limited number of charge/discharge cycles.

A long time ago I read that, because of advances in materials science, possibly with composites, they can make a flywheel that spins at 100,000 rpm without exploding.

This is a very efficient storage medium, and with all the "green" stuff lately, maybe someone is producing this thing. I think it spun in a vacuum to prevent drag.

It would have been used in cars, but people were afraid of this thing escaping in a crash. Or maybe the battery people had/have a strong lobby.
 

mivey

Senior Member
langjahr@comcast.net said:
...they can make a flywheel that spins at 100,000 rpm without exploding.

This is a very efficient storage medium, and with all the "green" stuff lately, maybe someone is producing this thing...
I hadn't heard of that 100k flywheel but I'll look it up.

I think some of the green people don't mind spending extra money as long as they feel that they have saved a tree in a rain forest somewhere. I have no problem with that if it makes them happy. What bugs me is when they want to spend my money trying to save a tree. Stay out of my pocket and let me decide what I support.
 

ghostbuster

Senior Member
langjahr@comcast.net said:
A long time ago I read that, because of advances in materials science, possibly with composites, they can make a flywheel that spins at 100,000 rpm without exploding.

This is a very efficient storage medium, and with all the "green" stuff lately, maybe someone is producing this thing. I think it spun in a vacuum to prevent drag.

. Or maybe the battery people had/have a strong lobby.
Flywheel technology(in vacuum) is used sometimes in larger U.P.S. systems.It replaces the need for batteries(it has been around for at least 20 years).

:)
 

dereckbc

Moderator
Staff member
ghostbuster said:
Flywheel technology(in vacuum) is used sometimes in larger U.P.S. systems.It replaces the need for batteries(it has been around for at least 20 years).
A Flywheel UPS is only good for a few seconds, or just enough time to allow the generator to start and take over.
 

cschmid

Senior Member
so is there any other technology available for solar applications outside of batteries..could you not run a DC motor that powers a generator..
 

dereckbc

Moderator
Staff member
cschmid said:
so is there any other technology available for solar applications outside of batteries..could you not run a DC motor that powers a generator..
That would be extremely inefficient. Solar PV systems already suffer about 66% efficient in terms of watts generated vs. what is used. Running a DC motor to turn a generator would add even more losses.
 

cschmid

Senior Member
how about we create a hot water system and have the system run a generator..you know the Boiler style system..
 
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