Archive for Wednesday, May 12, 2010

De Soto school adds solar, wind power

Shane Paulsen, left, and Troy Robinson, with The Energy Savings Store, were on the roof of Starside Elementary School in De Soto on Tuesday installing four solar panels and a wind turbine. The panels and turbine will be used not only to power a small part of the school but also to teach the students about sustainability.

Shane Paulsen, left, and Troy Robinson, with The Energy Savings Store, were on the roof of Starside Elementary School in De Soto on Tuesday installing four solar panels and a wind turbine. The panels and turbine will be used not only to power a small part of the school but also to teach the students about sustainability.

May 12, 2010


— The 2009 Kansas Green School of the Year just got a little greener.

On Tuesday, a crew from the Energy Savings Store put in four solar panels and started installing a wind turbine on the roof of Starside Elementary School in De Soto.

“This is so exciting,” Paula Henderson, the school’s counselor, said. “We’ve been waiting for years to do this.”

The panels and turbine are a part of the school’s efforts to reduce its carbon footprint while teaching the kids about sustainability.

Each solar panel will be able to produce about 175 watts of electricity. The amount of electricity produced by the panels and the wind turbine will be charted and put on display on the school’s website.

Henderson said teachers will be able to show their students how much power the panels and turbine have created that day or since they were installed.

She said the amount of energy the panels produce won’t be enough to power the school, but they bought a unit that can be expanded to produce more electricity.

The total cost of the panels and turbine was about $12,000. The school raised $3,000 for the project and received grant money for the rest.

The wind turbine’s energy will be used for another project that will begin this summer. Henderson hopes to install an electric train set behind a display case just inside the school that will be powered by the turbine. The train will travel around a green town and will make stops at the recycling depot or the houses of clay models that represent the Starside teachers.

“I think it will be a fun thing to watch,” Henderson said.

When not powering the train, the extra electricity will be used to charge rechargeable batteries for the school.

The solar panels and wind turbine are just a couple of things the school has done to become more sustainable. Besides a major recycling effort, the school has recently started an organic vegetable garden that uses the compost made in worm farms in the classrooms.


devobrun 5 years, 5 months ago

How much CO2 did it take to build, install and now operate these solar panels and turbines and batteries?

Will the net CO2 emission be negative? Nobody else has yet reduced carbon output. Why should you?

Oh, I see, the carbon is in China now instead of here in Kansas. Out of sight, out of mind. No really, you are out of your mind.

tomatogrower 5 years, 5 months ago

Quit whining and sell your oil stocks. There are other places to invest.

Kirk Larson 5 years, 5 months ago

The initial costs are eventually overcome (unlike non-renewable energy where you burn it and then it's blowing in the wind). My folks put up a solar water heater back under the first tax credit for solar (the one Reagan rescinded) and in a few years it was paid for and then continued to be used for nearly twenty years after. That's twenty years of gas that would have been burned but wasn't.

devobrun 5 years, 5 months ago

Hey Cappy, do you have an energy budget for that system? No Cappy, not dollars, joules of energy. The joules of energy used to build, install, and operate the hot water system.
Joules in and joules out. If you ignore the upfront energy costs, then it makes sense. But coal, gas, oil all were expended to build the system.

Are there any solar hot water heater companies in the world running their operation off solar power?

Oh, I like how you merely tossed out "it was paid for" and moved on. You mean it was paid for by the government to a company who used the money to buy electricity from coal to build the hot water system. You're being jobbed, Cappy. Scammed, Cappy. You are being pushed around by marketeers and flim flam men. If it worked, you wouldn't need a dollar subsidy.

Kirk Larson 5 years, 5 months ago

You're being overly simplistic. No, I don't know all the carbon ins and outs but I doubt that the initial input was greater than what the twenty years of service offset. And when I said "paid for" I meant that at that point my folks had saved enough on their gas bills to cover the initial cost of the system (which I'm sure included the dollar cost of the energy it took to construct it) and the solar energy utilized beyond that point was gravy. You just seem to be one of those wingers intent on bad mouthing renewable energy whatever the economic circumstances.

just_another_bozo_on_this_bus 5 years, 5 months ago

"But coal, gas, oil all were expended to build the system."

In a world that runs on coal, gas and oil, any and every system implemented will do the same. Including oil derricks, coal mines, gas wells, you name it. Energy inputs will always be required to do any type of work. (That's kind of the definition of work, isn't it?)

But at least once enough solar and wind-powered generators are in place, there is at least the possibility that future "energy budgets" will have either no or greatly reduced carbon-based inputs. Doing the same ole same ole just means more of the same ole same ole. But that seems to be what you want.

grammaddy 5 years, 5 months ago

Great idea! This is the message we should be sending our kids.Great way to get them involved in the "Green" movement.

GardenMomma 5 years, 5 months ago

The kids raised $3,000 and the school received a grant for the rest. The article doesn't say where the grant came from, but I bet it wasn't from the school district. It probably came from the federal government.

As for "real subjects" I suppose tracking how much energy is produced is called science. That's not a real subject? What is a "real" subject to you?

jhawk0097 5 years, 5 months ago

"As several people here have noted, it costs more energy to make these solar panels than will ever be recovered from the sun during their lifetime."

Link? That's total bs. Get your mind off global warming. Cleaner energy is a good thing regardless.

grammaddy 5 years, 5 months ago

Start up costs are always high. This is fairly new. As more people do this the cost will come down.

Chris Golledge 5 years, 5 months ago

Not a big deal, but your math is a bit off.

"...the Energy Savings Store put in four solar panels..." "Each solar panel will be able to produce about 175 watts of electricity." "The total cost of the panels and turbine was about $12,000. "

It's not $12,000 for one panel.

Not sure if they are 100% right, but the figures that I've heard indicate about a 7-year payback for solar panels in terms of energy put in to making them versus energy gotten from them. In contrast, a hydroelectric damn might have a 100-year payback. I don't have figures on wind turbines.

In any event, when is education not an investment with little short-term gain? It's clear to me that this is a project aiming for long-term paybacks, and the educational aspect is larger than the energy cost savings.

gphawk89 5 years, 5 months ago

Someone beat me to the "it will power about one computer" comment. Throw a laser printer in and the output of the entire system would be inadequate.

I'm not against doing something like this to teach students about alternative energy by any means. But hopefully the website that charts the power output will contain enough information to put things into perspective. It should include bits of information like how many solar panels would be required to power the entire school, how much that would cost, and how much physical area would be required for said panels compared to the area of the roof of the school.

devobrun 5 years, 5 months ago

Each solar panel produces 175 watts max. They aren't producing 500 watts total today. Nor will they tonight, or any other night. The article doesn't say how much the turbine produces, nor the size (in joules or Volt-coulombs) the batteries hold.

The $12,000 expenditure went to a coal-fired electricity plant that supplied the electricity to build the system. Silicon processing into solar cells is quite energy intense. The additional money for the workers goes to gasoline for their trucks and other energy needs of the workers, all from conventional sources of fossil fuel.

I see no description or picture of the turbine. I wish I did so I could comment, but......

These solar panels are fixed (not tracking). Thus the power out is proportional to the cosine of the solid angle made by a line perpendicular to the panel and the rays of the sun.

Unless the picture is fooling me, this looks like a low-pitch roof. Maybe a 5/12 roof or 25 degrees. In the summer at 39 degrees latitude the sun will hit the panel very nearly straight on at noon. Therefore the total energy throughout the day is the integral of a cosine from zero to pi, divided by pi. That is 32%. But that is for a half a day, so the total energy from the panels would be half that, or 16%. So:

Summer day energy is 500watts times 3600 seconds per hour time 24 hours times 0.16.

6.9 million joules of energy per day.

In the winter, the sun angle is low and the sun is up for only about 9 hours. The panel duty cycle would drop by an additional 50%.

3.5 million joules of energy per day.

The DC to AC inverter will run about 80% efficient. The cloudy days will drop the output by another 66%. (Generous) If batteries are used to store most of the energy, then recover it, figure about 50% charge/discharge efficiency.

So figure a total of about 25% efficiency of the storage and conversion system and clouds. (.8 times .66 times .5)

If I average the winter and summer energy expectations, I get about 5.2 million joules and decreasing for storage and clouds, I get an average of 1.3 million joules of energy per day.

That's 475 million joules of energy from the solar panels per year.

Sounds like a lot, but let's figure a kilowatt-hour is 3.6 million joules. That's 132 hours @ 1kw. That's about 5 1/2 days of 1 kilowatt per year.

You pay about 10 cents per kw-hr.

That's $13.20 per year.

Pays for itself in 91 years, not counting the time cost of money.

The worst calculation, though is the energy budget. This setup will not produce more energy than it took to build and install it.

Don't bother.

just_another_bozo_on_this_bus 5 years, 5 months ago

From the article--

"The total cost of the panels AND turbine was about $12,000."

I know that's just a little detail. I'm sure that you were wholly honest in your calculations otherwise (sarcasm.)

devobrun 5 years, 5 months ago

And you would know, Bozo. You would know.

jhawk0097 5 years, 5 months ago

Among other things, I doubt their system has batteries. It's probably tied to the grid.

LogicMan 5 years, 5 months ago

That $12,000.00 would have paid for a lot of weatherizationwater-savingetc. for the school, and given a much faster pay back and a better lesson. But it might be too logical to do?

devobrun 5 years, 5 months ago

Logic, check this out from the article: "The panels and turbine are a part of the school’s efforts to reduce its carbon footprint while teaching the kids about sustainability."

The lesson is that their teachers can't do physics or business. The lesson is that "green" technology is not about reality. It is about demonstration, intent, good feelings and good will.

Actually saving energy and actually being responsible would involve caulking windows, managing window blinds in the summer, walking around the school and reducing lighting in areas where there doesn't need to be as much light. Making sure that all faucets turn completely off. You're right, Logic. That $12k could go a long way.

If they have a gym in the school, they have lights out the wazoo. Being careful about when those lights are on and leaving them off unless needed would save more energy than anything else. Just a few lights to keep it safe until gym class.

Not only that, but the electric bill could tell the tale of whether the conservation efforts were helping. Make it a contest. Have fun, learn. Don't just drink the green cool-aide. Think.

Chris Golledge 5 years, 5 months ago

Devo, For a guy who puts no faith in models, what you have above looks an awful lot like one.

Meanwhile, here is actual data from a guy in Texas who is getting about 12 kW h per day out of a PV system. The De Soto system is about 4/18th (2/9 = 0.222) the size of his.

Granted, that's Austin and not De Soto, but it should be in the same ballpark. It's not like comparing Portland and Phoenix.

12 kW h per day * .222 = 2.66 kW h per day is a ballpark figure for what to expect out of the De Soto system.

At ~10 cents per kW h, 2.66 kW h per day * 365 days, they should save about $97 per year. Mmm, that's before the inverter; so, using your figure of 80% efficiency on the inverter, about $80/year. That's still not really exciting compared to some other green options, like a ground-source heat pump versus a traditional furnace + AC (I'm in the positive about $100/month since putting in a GSHP last fall, versus propane.), but it's a lot better than your model would indicate.

I suspect most of the lights and computers are on during the day when the sun is shining and off at night, when it is not.

Batteries with a PV system really only make sense if there is no grid. There is a grid; so, let's assume no batteries until we know otherwise.

I'm thinking that whoever is selling the PV panels must be selling them at a cost that at least covers the cost of the energy used to produce them. But then, do glass manufacturers pay the same price for energy that you and I do? Hmm, probably not, so the question of energy in versus energy out remains unsettled.

Too bad they didn't break out the cost of the panels versus the turbine for us numeric types.

Chris Golledge 5 years, 5 months ago

Batteries are expensive and wear out. The additional cost simply isn't worth it in applications were grid power is available. This is true with or without net metering, based on what I've read.

devobrun 5 years, 5 months ago

This comment was removed by the site staff for violation of the usage agreement.

just_another_bozo_on_this_bus 5 years, 5 months ago

"Politics, love, desire, emotion."

And Devo would have us believe that he's immune from such things, when it's clearly his prime motivator.

devobrun 5 years, 5 months ago

Of course I am not immune to emotion, bozo. In my case however, I know the difference between cold hard calculation and emotion. Just because I show emotion doesn't mean that I can't think.

You however have yet to demonstrate the difference between the two.

just_another_bozo_on_this_bus 5 years, 5 months ago

"Of course I am not immune to emotion, bozo."

Thanks for that, Sherlock.

"Just because I show emotion doesn't mean that I can't think."

I don't doubt that you can think. I agree that so-called green technology shouldn't just be given a free pass just because it claims to be green, but picking on a demonstration project at a small-town grade school as somehow representative of the whole industry isn't going to give us much useful information.

I could give you more credibility if you were willing to give the same level of scrutiny to old-line technologies, externalized costs and all. But that appears to lie outside your ideological boundaries.

devobrun 5 years, 5 months ago

cg, I just read your post more carefully. If the De Soto system is 1/2 kw peak and it can operate over an average of 12 hours per day, that's 6kw-hrs. That's absolute maximum.

For a system directly pointed at the sun for the entire time the sun is up. No clouds.

The De Soto system doesn't track the sun, and It gets cloudy in Larryville.

It is way less efficient because it doesn't live in Austin and track the sun.

OK, so your going to get 2.66 kw-hr per day out of this system? A 1/2 kw system at max output? That's an average of 5.3 hours of maximum output per day, every day of the year. On average, the sun is "up" 12 hours a day. That's a maximum possible of 6 kw-hours per day from the De Soto system. That's when there are no clouds and the system tracks the sun, and there are no breakdowns, troubles, etc.

5.3/6 = 89%.

89% of maximum, cg. From a non-tracking solar panel in Kansas.

If your link guy has a system that delivers an average of 12 kw-hrs per day over a year, good for him. He doesn't do it with 1/2 kw solar panels. It is impossible.

Unless he lives where the sun shines 24-7.

You missed the tracking part. You missed the 12 hour day part. You dismissed the cloudy in Kansas vs cloudy in Austin part.

My numbers stand. OK, its $15 a year instead of $13 a year. Heck, I'll make it $20 bucks a year and it pays off in only 60 years.

The grid. Efficiency of the inverter is not 80% when attached to the grid. Phase angle issues make the inverter a slave to the grid frequency and phase. It is more like 70%.

And if we all have little power generators, managing the grid will be an exercise in chaos theory. And the overall grid efficiency will go down for all of us, including the coal-fired plant.

Read this from an old friend of mine. He is a retired British professor of Electrical Engineering at U of Manchester. Pity the poor grid controller.

Finally, your comment about cost of energy is moot. It isn't cost in dollars. It is cost in joules. The energy needed to smelt silicon, diffuse the proper impurities and then sputter the contact wires on these babies is large.

I was the lab director at KU in the EE solid state lab in 1976 and 1977. We did it. We made the diodes. The ovens were around 850 Celsius. It was hot.

Oh, the energy in versus energy out for silicon solar cells is not uncertain. The cost break point (in joules) is 16 years. But the installation and further degradation due to not pointing the panels at the sun and clouds makes the numbers go to something like 60 or 90 years.

It's a lie.

Chris Golledge 5 years, 5 months ago

And you missed the part where actual measurements were used rather than hypothetical calculations.

BTW, 4 * 175W = 700W; that is the De Soto system. So, I'm not sure from where you are getting the 500 W system example. And, if you read a little more carefully, you would have seen that my sample uses 18 180W panels, compared to 4 175W panels in De Soto. Neither system tracks the sun.

You said I was wrong; can you point out where I'm wrong in projecting my estimate of energy produced?

lounger 5 years, 5 months ago

Regardless of you fuddy duddys this is a step in the right direction and is investing in the future.

blakec 5 years, 5 months ago

My feelings exactly lounger. Because everyone knows coal and oil are going to be around forever. Cheap solar is being developed as we speak. The iJET cell is really exciting and hopefully it comes to fruition soon. Cheap solar energy is around the corner because gasp some people refuse to accept the status quo as the absolute.

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