"Green" DIY - slim pickings

[Dan Karachio]

The last thing I am is a crunchy granola type, but after seeing so many cool alt energy systems on This Old House I did a little researching yet it leaves me depressed. Wouldn't it be cool to have a solar thermal system that heated a large portion of your water or house? How about solar voltaic managing up to 75% of your electrical bill!

Sounds great, but there seems to be a real void of affordable, scalable and useful products out there as well as a void in well presented information for the DIY in retrofitting existing houses. For example, solar voltaic systems would run about $40,000! Sure you can get tax credits (lots of headaches there I assume) and the relative price comes down to 25-30, but please. Seems to me the current market serves people with tons of money and it's more of a "feel good" kind of thing vs truly making a dent in energy consumption. "Oh yes, Rutherford the III and Buffy outfitted their summer home to be completely green and sustainable..."

On the opposite end the DIY stuff I have seen is very crude and nowhere near as effective. I know new technologies have a way of scaling down over time to be more affordable, but it seems a long way off.

Wouldn't it be nice if there was a more "modular" approach that was also a little more DYI? If that existed I could see myself and many others getting their feet wet at 3-5,000 then add various components as time went along. As far as I can tell it just doesn't exist.

Somewhat related, I am little tired of everything "green" costing 2-5 times as much. I'm sorry, but I smell scams and gouging.

[Eric DeSilva]

My Dad just had a photovoltaic system installed in his house. Think the total cost ran about $25K, but with all the tax breaks, etc., it ended up costing him only about $3K out of pocket. I looked into it in my area and the tax breaks weren't nearly as advantageous. But, might be worth digging a bit.

[Dan Karachio]

Wow, that's pretty amazing. Can I ask what state he is? I'm in PA, but I am almost sure nothing like that is available. A radio show discussed this and said with tax and other incentives you could knock a $40k system down to 30ish or a little lower. Payoff on something like that is out of this world.

[Dick Strauss]

Dan,
I think geo-thermal systems are a good investment for folks in hot or cold climates. IIRC my cousin told me his system cost $6-7k for the complete system (for a 2400 sq ft house). His heating/cooling bill now averages $900/year (including extra electricty for the pumps). He had been spending 2-3x that with his traditional heating/AC system. When you consider what a complete heating/AC system costs (say $5K), I think he figured it would pay for itself within a year or two. If I had the space in the yard, this would be at the top of my list!

Like anything...I think once more people are doing it, the cost premiums will come down in time.

[Frank Hagan]

Solar works if you have the state tax incentives, utility rebates, etc. Here in California you can "lease" a system for 20 years at your current electric bill amount, effectively locking in your current payment. No upfront cost. The electric utilities are compelled to "buy back" excess power that flows back into the grid (but never below $0), so the leasing company is working on the float between the electric bill and how much your monthly bill is. Its probably not as good a deal as it sounds like; at $100 a month for electric, you're still paying $24,000 over the life of the lease. And I don't think you own it at the end, so you might have a huge increase in the monthly fee at the end of 20 years.

Part of the high cost is that the panels have to be hooked to a disconnect the electric utility can control, so that if their power goes out, and a lineman goes out to repair something, he doesn't get zapped by your "backfeed" into the grid. You get into some very expensive controls, in addition to the high cost of the panels themselves.

[Jeffrey Makiel]

We are looking into a solar panel system at my workplace. It's a sizeable investment of over $8 million. Tax incentives are the only thing that makes photovoltaic systems economoical even in NJ which has one of the highest electric rates.

However, I must say that the tax incentive (called renewal energy credits, or RECs) skews the real economics of these systems. Further, if my workplace receives tax discounts, that means somebody else must pay more in taxes.

Seems like another version of a Ponzi scheme.

-Jeff :)

[Eric DeSilva]

Wow, that's pretty amazing. Can I ask what state he is?

He is in MD. I can ping him and see if he can list the types of incentives that he applied to the purchase.

[Lee Koepke]

The last thing I am is a crunchy granola type, but after seeing so many cool alt energy systems on This Old House I did a little researching yet it leaves me depressed. Wouldn't it be cool to have a solar thermal system that heated a large portion of your water or house? How about solar voltaic managing up to 75% of your electrical bill!

Sounds great, but there seems to be a real void of affordable, scalable and useful products out there as well as a void in well presented information for the DIY in retrofitting existing houses. For example, solar voltaic systems would run about $40,000! Sure you can get tax credits (lots of headaches there I assume) and the relative price comes down to 25-30, but please. Seems to me the current market serves people with tons of money and it's more of a "feel good" kind of thing vs truly making a dent in energy consumption. "Oh yes, Rutherford the III and Buffy outfitted their summer home to be completely green and sustainable..."

On the opposite end the DIY stuff I have seen is very crude and nowhere near as effective. I know new technologies have a way of scaling down over time to be more affordable, but it seems a long way off.

Wouldn't it be nice if there was a more "modular" approach that was also a little more DYI? If that existed I could see myself and many others getting their feet wet at 3-5,000 then add various components as time went along. As far as I can tell it just doesn't exist.

Somewhat related, I am little tired of everything "green" costing 2-5 times as much. I'm sorry, but I smell scams and gouging.
That technology isnt that far off. Example, I researched a startup company that is providing prototype solar film to military now. Its bascially a solar panel embedded in 15 mil film. It can be applied to windows, awnings, and for the military, tents. It works on almost the full spectrum of light, so installing the film on the interior of a building window, it generates power from the interior lights as well. Now, it will take awhile to get to market, but it is moving forward.

Like it or not, $4 + / gallon gas has made more people aware of energy. Commercial buildings use 60%+ of all electricity and at least that much of our water. residential is WAY down the list. So the market is geared towards commercial. Until more competition hits the marketplace, these current vendors will rule.

IMO ( and only my opinion), the GREEN products tend to be better quality, thus more $$. Our society still has not been able to put it in the pro-forma to pay a premium for quality in most situations. So again, you get what you pay for.

Part of my job is helping Owners understand LIFE CYCLE costs of buildings. If you spend 10% more on your building, but recoup that expense in 5 years kinda thing.... its real hard for them to see the long term cost in light of the upfront capital outlay.

[Pete Simmons]

"Part of the high cost is that the panels have to be hooked to a disconnect the electric utility can control, so that if their power goes out, and a lineman goes out to repair something, he doesn't get zapped by your "backfeed" into the grid. You get into some very expensive controls,"

-----------

Where I live in Florida the power company will decrease your bill around $7 or $8 per month if you agree to a switch on your water heater so they can switch it off remotely if demand gets to high. So this remote switch must not cost much as there are lotza them in use right now in Florida. As far as I know in about 8 years of use they only switched us off once for a few hours.

As far as selling self generated solar power back to the utility that is a long way off dream. First you will never get much more than about 100 watts per sq meter of surface area. Then you need to convert that into nice clean 60 cycle AC - That is where you can spend some big $$. Oh Yea - I almost forgot this only works about 6 or 8 hrs per day if it is not cloudy.

You can read more about this at my website

Fuelfrenzy.com

No ads, nothing for sale. Just info on energy. I welcome anyone to point out any errors in the numbers used there. I will gladly correct any errors.

[Pat Germain]

On the Green DIY front, two of my coworkers who live out in the country were seriously considering buying instructions from a web site for building a wind generator. This generator is a retrofitted auto alternator. Basically, you bolt a radiator fan to an alternator and, zzzziiiiiiing, you got a wind generator to power your house! And it's good for power failures as well as reducing your electric bill.

My coworkers could not understand my skepticism in such a concept. I'm no electrical engineer, but I know enough about cars to understand that an alternator puts out about 14 volts at most and it's Direct Current. So how is this supposed to power a house?

Apparently, you're supposed to connect this wind generator to a bank of auto batteries. Well, here again, you're putting out 14 volts DC. I know you can buy AC converters which will connect to a car battery and run an electric drill, for example. And you can connect the batteries in series to boost voltage.

But in a power failure, what you want most is water from your electric well, a functioning refrigerator and a working washer and dryer would also be nice. I still don't think "the brave little alternator" is going to do the job. And how would you tie it into an existing home electrical system to save money?

I could see a wind powered alternator providing some lights in a power failure. But anything more is just fantasy. I have a friend who installed a huge, gasoline-powered generator when he built his house east of town. Yep, that thing works! His neighbors always call him when they see his house lit up during a power failure. "How come you got power up there?"

[Kyle Kraft]

I get calls from people all the time looking for wind turbines. With todays electric rates the payback time is 8-10 years at best. The other hurdle is your township government. Most times they won't let you have anything taller than your house without an act of Congress and a note from your mom.

[Pete Simmons]

You probably know someone who plans their energy independence around a home windmill. At less than 5 watts per sq foot in a 10 mph wind you can see it is not going to happen.
Lets use a 10 foot diameter windmill. That works out to about 78 sq feet of wind area. Which equals about 400 watts of pure wind power at 10 mph.
From this 400 watts losses quickly start to steal power from your system. Rotor, generator and storage losses reduce your available to maybe 50 watts. Just enough for a small light.
Many people seeking energy independence were led to believe that their small wind generator would generate so much power that they would be able to sell the excess back to the power company. There are a few problems with this idea.
1. Very few (read NO ONE ) will ever generate enough power for their own use. Never mind selling the excess back. 2. Most (read NONE ) small wind generators do NOT generate power that is of a quality acceptable to a power company grid. They want/demand clean 60 cycle AC current which is very difficult and/or very expensive to generate with a small wind generator.

[Frank Hagan]

Where I live in Florida the power company will decrease your bill around $7 or $8 per month if you agree to a switch on your water heater so they can switch it off remotely if demand gets to high. So this remote switch must not cost much as there are lotza them in use right now in Florida. As far as I know in about 8 years of use they only switched us off once for a few hours.

As far as selling self generated solar power back to the utility that is a long way off dream. First you will never get much more than about 100 watts per sq meter of surface area. Then you need to convert that into nice clean 60 cycle AC - That is where you can spend some big $$. Oh Yea - I almost forgot this only works about 6 or 8 hrs per day if it is not cloudy.


Here in California, the utilities are required to buy back excess electricity, but your bill never goes below $0 (in fact, there's a nominal "connection fee" that is $10 or $15 per month). I have corresponded with several people who have only the nominal fee on their bill year round ... one that I corresponded with finally disconnected from the grid entirely (he spent the extra for a large battery bank, so its doubtful he'll recoup his money anytime soon). So in the right place, solar can indeed provide all the electricity you need, and the "buy back" feature allows you to time-shift your electricity usage to nighttime (in the sunbelt, more electricity is used in the daytime than the nighttime, so this works out for the utilities as well). You sell the electricity during peak rates ... when the sun is shining here in the sun belt ... and any extra you need to use is during off-peak.

I could dig out the details, but the "switch" I was talking of does include an inverter/converter to feed the power back ... and none of that is cheap. Here's a quote from one of the guys I corresponded with about his system that not only supplied his household power but also charged his electric RAV:



Our first year of generation came to a close on July 31, 2004. We did better than expected! Our average production was about 400 kWh/month. After one year of living in the house and a year of driving 13,000 miles in the Rav, we had a net excess of electric credit. In fact, we not only left a $25 power credit on the table, we also left the $65 of minimum charges on the table as well. That is $90 worth of energy credit that we effectively handed over to PG&E for the privilege of being part of the solution. That $90 is about 2.5 months of power for us these days! Next year I won't be so stingy with the AC!

From his web page at http://evnut.com/ ... click on "Solar" in the left menu.

[Dan Karachio]

It's tough out there. I'm just looking for a reasonable DIY project where I can contribute something to my house's energy costs, but right now unless I want something totally DIY or want to spend mega bucks, there just isn't much out there. Alas, building a new house with this stuff would be far more doable than retrofitting an old house.

[Pat Germain]

On my way home from work every day I drive by a house where two solar panels were recently installed. They are mounted on stands in the back yard and somehow the panels move to follow the path of the sun.

I don't know anything about those solar panels, but they sure look expensive. I'm wondering how much juice they actually squeeze out of sun power.

[Frank Hagan]

It's tough out there. I'm just looking for a reasonable DIY project where I can contribute something to my house's energy costs, but right now unless I want something totally DIY or want to spend mega bucks, there just isn't much out there. Alas, building a new house with this stuff would be far more doable than retrofitting an old house.

That's true. About the only DIY thing that is really doable is solar hot water heating. Once you get into interconnecting with the utility company you get into a whole different area requiring expertise.

That's ignoring the areas where you get the most bang for the buck, making sure your insulation is adequate, reducing your water heater temperature, using a set back thermostat, plugging your chimney if you're not using it, etc. Those measures usually get you a payback within a year or two.

[Eric DeSilva]

He is in MD. I can ping him and see if he can list the types of incentives that he applied to the purchase.

Whups. I seem to have gotten numbers wrong. He had a 1.7 kW system installed for, as it turns out, $15K. There was (in 2008, dunno if its still good) a $2K fed tax credit. He also got a $5K county ppty tax credit and a state rebate of $2.5K/kW, so about $4.5K. So, $15K system for $3.5K.

That said, he's now questioning, with MD budget issues, whether he is going to see the state rebate at all...

[Thomas Bank]

That's true. About the only DIY thing that is really doable is solar hot water heating. [snip]

That's ignoring the areas where you get the most bang for the buck, making sure your insulation is adequate, reducing your water heater temperature, using a set back thermostat, plugging your chimney if you're not using it, etc. Those measures usually get you a payback within a year or two.

Frank is pretty spot on. Although on-site electrical generation - whether wind, solar, fuel cell, whatever - is "sexy" it isn't practical in most cases due to the relative newness of the technology. You're looking at higher costs due to limited production and R&D costs.

We advise our clients to concentrate on making the most use of "old school" technology first - insulation often being the most cost effective payback along with sealing leaks. Finding someone who can do a blower door analysis of your building can be an effective payback. From there, we've done geo-thermal heating systems with good results - both residential and commercial. As more are done, the "premium" for the wells is coming down in cost. Automation - programmable thermostats and motion activated lights and faucets and such - started off in commercial use but are becoming more common in residential as well. Most homes with kids can understand the advantages of faucets and lights that turn themselves off. ;)

Although solar electrical generation is still a bit on the leading edge, solar heating is much more proven. Even a system to pre-temper water can have advantages.

My next personal project along these lines is looking into solar heating for the shop. I have radiant tubing in the concrete slab for the first floor and baseboard hot water for the second floor. I'd like to connect in a couple solar panels to temper the space. I figure that I can likely keep it in the 45° to 55° range and then when I'm out there use the boiler to raise it up to working temperatures. On the level of daydreaming at the moment, the next step would be whether a vertical axis windmill would generate enough energy to power the circulation pump when the heating system was in "tempering" mode.

[Pat Germain]

... the next step would be whether a vertical axis windmill would generate enough energy to power the circulation pump when the heating system was in "tempering" mode.

You may not need it. A friend of mine installed a solar water heater for his swimming pool. It required no pump of any kind. Apparently, the heating action of the solar panel automatically caused the water to circulate from the pool to the roof and back into the pool.

I think this is similar to old fashioned steam boilers and radiators. There was no need to pump the steam. It rose on it's own, then came back to the boiler when it cooled off.

[Thomas Bank]

Since the rest of my system is already in place with a boiler and circulation pump, I'd need to run the circulation pump for the "solar tempering" mode as well.

I have seen the solar heaters that work by convection within the system and no pump, though.

[Craig Kershaw]

It seems to me that most of the stuff you see on green energy revolves around large scale projects that merely enable the large corporations to sell consumers electric derived from green sources rather than traditional sources. While these are good for the environment they don't lower anybody's electric bill. As The WHO said, meet the new boss, same as the old boss. Big government/business don't really want consumers to go off the grid, for craps sake they'd go out of business now wouldn't they?

Once device that gets little press is a device called a solar air heater. Not only don't they get any press they also don't get any tax rebates, at least in Maryland. These things are very simple, basically just a black painted box through which cold air is fed into at the bottom, runs through maze of sorts, and exits out the top. A company in Canada sells a commercial unit called a Cansolair, one costs about 1,500 and can heat about 1100 square feet. Their website interviews a guy in Newfoundland, where is it is very cloudy, the guy says his heating system rarely runs in the daytime.

[Pete Simmons]

I had solar hot water for years in New England. On a cold winter day with just a little sun I would get 140 degree liquid out of the collectors.

Easily got around 90% of our hot water needs from it.

Many versions of home solar hot water systems can be easily homemade.

[Eric DeSilva]

Turns out the Fed Tax credit is still good, and is not capped (for solar) at $2K:

Residential Renewable Energy Tax Credits
Consumers who install solar electric systems can receive a 30% tax credit for systems placed in service from January 1, 2006 through December 31, 2016; the previous tax credit cap of $2,000 no longer applies. In addition, consumers who install small wind systems can receive a tax credit up to $4,000. Geothermal heat pumps also qualify for tax credits up to $2,000.

From http://www.energy.gov/taxbreaks.htm

[Chris Padilla]

You may not need it. A friend of mine installed a solar water heater for his swimming pool. It required no pump of any kind. Apparently, the heating action of the solar panel automatically caused the water to circulate from the pool to the roof and back into the pool.

I think this is similar to old fashioned steam boilers and radiators. There was no need to pump the steam. It rose on it's own, then came back to the boiler when it cooled off.

I have a solar pool water heating system on my roof. I had it installed 1 year ago and used it last summer. It most assuredly requires a pump to get water up to the roof of a two story house but I'll be darned if the water coming out isn't pretty darn hot! We had a nice season of swimming. Now if I could just run the swimming pool pumps on pure solar, that would something!

The pool heater is nothing more than black PVC bolted to the roof of the house. There is a large 2" feeder pipe and the same return pipe. Between the two are hundreds of very small diameter tubes. That is it. It is a Fafco system so you can probably look it up.

[Dan Friedrichs]

The real problem with solar PV is that, while the cost of the inverters and controls will go down with increased production, the cost of the solar cells themselves comes mostly from the expensive processing necessary to manufacture them. PV cells are nearly entirely just silicon (sand), but to process and purify the Si to the necessary extent for effective PV cells requires a LOT of time and energy. A typical PV system will make back 5x the amount of energy it took to create in its lifetime.

A wind turbine system, on the other hand, will generally make back 30x as much energy as took to produce it.

If you really want to do something "green" and DIY, I think building a small wind turbine is a great project. The idea of using a car alternator is really, really bad (you need separate field excitation, and they need to spin really fast to make any power), but building simple permanent-magnet generators is easy - see otherpower.com (*no affiliation or endorsement)

[Pat Germain]

I recently saw a headline about a UFO collision being blamed for destroying a wind turbine. So, I guess there's that risk to worry about with a wind turbine. ;)

[Frank Hagan]

You may not need it. A friend of mine installed a solar water heater for his swimming pool. It required no pump of any kind. Apparently, the heating action of the solar panel automatically caused the water to circulate from the pool to the roof and back into the pool.

I think this is similar to old fashioned steam boilers and radiators. There was no need to pump the steam. It rose on it's own, then came back to the boiler when it cooled off.

Don't think so; hot water rises, and stays there until it cools. In the old steam systems, the steam cooling, going through the phase change back into water caused it to fall. I suspect your friend didn't require an additional pump, and used the existing pool pump. The friction loss of pumping the water up onto the roof (15' to 20' of head) is compensated for by the gain of the water going down off the roof. So the only calculation that needs to be done is for the friction loss through the length of pipe up and down, and the panels themselves. They add a couple of thermostatically controlled valves, the piping and the panels, and you save the money on the pump.

You can have a passive, themo-siphon solar panel, but the panel has to be lower than the pool. It then uses the "hot water rises" principle to keep the hottest water in the pool and avoids making the solar panel a giant radiator at night. There are some domestic water heating units that use this principle; they have a big tank at the top of the panel itself.

[Frank Hagan]

The real problem with solar PV is that, while the cost of the inverters and controls will go down with increased production, the cost of the solar cells themselves comes mostly from the expensive processing necessary to manufacture them. PV cells are nearly entirely just silicon (sand), but to process and purify the Si to the necessary extent for effective PV cells requires a LOT of time and energy. A typical PV system will make back 5x the amount of energy it took to create in its lifetime.


There are some new technologies that "print" solar cells on mylar using a process similar to inkjet printers. One California company is actually producing them, and using them for large, industrial projects. It reduces the cost of the solar cell drastically. We won't see them supplied for residential applications for a long time, and they are not a DIY item, but cheaper solar cells are coming.