THanks for the website.
I found the following there:

Incentive Type: Personal Tax Credit
Eligible Renewable/Other Technologies: Passive Solar Space Heat, Solar Water Heat, Solar Space Heat, Photovoltaics, Fuel Cells
Applicable Sectors: Residential
Amount: 25% for solar-electric and solar-thermal systems; 20% for fuel cells
Maximum Incentive: $3,750 for solar-energy systems installed before 9/1/06; $5,000 for solar-energy systems installed on or after 9/1/06; $1,500 for fuel cells; $6.00/W maximum qualified expenditure for solar-elelctric systems
Carryover Provisions: Excess credit may be carried forward five years
Eligible System Size: 10 kW maximum for net-metered solar-electric systems; 25 kW maximum for fuel cells
Equipment/Installation Requirements: Systems must be new and in compliance with all applicable performance and safety standards
Website: http://www.tax.state.ny.us/
pdf/2004/fillin/inc/it255_2004_fill_in.pdf
Authority 1: NY Tax Law Article 22, sec. 606 (g-1) and (g-2)
Date Enacted: 8/2/97 (solar electric)
Effective Date: 1/1/98 (solar electric); 1/1/03 (fuel cells)
Authority 2: S.5252 (2005)
Date Enacted: 8/2/05 (solar thermal)
Effective Date: 1/1/06 (solar thermal)

.........

Now, it does say passive solar heat. Would this be considered a solar Thermal system?
Would we be able to get credit for about 25% of the cost of building the unit then?
Also Does someone come and look to see if you built the space a certain way? It doesn't seem to mention that.
thanks!!!
-renee

I had two thoughts for the passive heat solar collector. i haven't done much reading as of yet as i just found out about the tax credit.
However the first one is to have a fan connected to a thermostat that blows the warm air in the house when the heat goes up to a certain temp.
the second thing is to remove the siding on the inside of the greenhouse (it is ugly) and build a more attractive brick wall there. This will be able to warm up in the sun and therefore keep the greenhouse/house warmer longer. I have seen that method used in older greenhouses.
i think I am going to call a local company that builds glass enclosures and ask them if they are aware of this credit. I read somewhere that I have till 2007 to have the project finished but i am not 100% sure on that.
this is pretty exciting to hear that there may be a tax credit. I have been wanting to do this for a long time and this would really help me out. Right now my plants are under light stands (such a waste of $$) so this would give me alot of savings hopefully. I am hoping to have money left over to buy a little solar panel to run the greenhouse fans and lights also.
Getting rid of all those stands will really help us out. I feel stupid saying that we try to be environmentally aware and not use a dryer and use a pellet stove for heat and other stuff and then people come to my house and see my light stands!
-renee

arrg! the glass surround company has no idea about the tax credit.
Do you know who I could contact for more information? The government site doesn't give me all the information I need. (or it does but it is written in confusing tax lingo and I am just not seeing it!)
thanks!!!!
-renee

Hi,
There is a tradeoff between a greenhouse designed primarely to raise plants and one designed primarely for house heating. To get maximum house heating, you would build a greenhouse with as little thermal mass as possible. With little thermal mass, it heats up quickly, and while the sun is shinning you transfer this heat to the house fast enough so that the greenhouse does not go overly high, which would increase losses to the outside. After sunset, you close off the greenhouse, and let it cool down -- since it has little thermal mass, it will cool quickly, and, if you are in a cold climate it would drop below freezing and kill plants.

For a greenhouse designed mostly to riase plants, you add thermal mass to the greenhouse. This heats up during the day, but the heat that goes into the thermal mass is then not available for house heating -- so you get less heat to the house. At night the extra thermal mass in the greenhouse keeps the temperature up and may be enough to keep the plants alive -- although some heating may still be required. Ideally, a plant growing greenhouse has some form of insulating curtains that that can be put in place at night to reduce the heat loss.

You can have a greenhouse that both provides some house heat and plant growing, but you won't get as much house heat out of it as one that is designed only for house heating.

The Shapiro book that I mentioned before, covers all this in good detail, and provides design procedures each type of greenhouse for various climates.

On getting more info on the tax credit, maybe your states web page that describes the program has a phone number?

Gary