Integrating Solar Thermal w/existing HW baseboard

[Joe Dozzo]

Greetings All,

I'm new to the forum and am looking for some help in setting some realistic objectives in converting our house to solar energy.

Our house in the foothills west of Denver CO already has a gas furnace to power the hot water baseboard heat in the house. According to our public service bills, we use ~800 therms/month with a range of 600 to 1100.

In soliciting bids for solar thermal, I've had one person suggest that a solar system could be nicely and cost effectively integrated into the existing furnace / baseboard system. Other contractors have said no way, it can't / shouldn't be done.

Both seem to make credible arguments but I don't have sufficient experience in this arena to make an informed decision. Any help would be greatly appreciated.

Thanks!

[Paul Bailey]

Hi Joe : Welcome to the group.. Denver stats tell me that your heating Degree days are ~ 6000 and , the Cooling degree day numbers are about 1000. Are your therm Numbers correct . Can you explain your present heating system in more detail ?? and its efficiency? Is this a very large house ? 800 therm in a month is ALOT unless your heating alot. Can you possibly heat with lower temps for better efficiency??? Paul:) May be out for the next couple days so i'll give you a more detailed reply later!!

[Joe Dozzo]

Hello Paul,

Our house is about 3000 sq ft on 3 levels, one with a large vaulted ceiling. I'm real new at this and am not sure how to translate the therms reported on our utility bill to degree days. I'll post our monthly usage over the last couple of years from home this evening.

Current home heat is supplied via a ~22yr old Burnham gas fired hot water heater and delivered to 4 independently controlled zones - each using baseboard registers.

Cooling is real old fashioned... We open doors / windows...

Southern exposure is excellent.

Regards,

Joe

[Frank Flynn]

Joe,

Many contarctors will recomend that you avoid things that they do not know. It might be good, valid advice to avoid doing this in your case or it might be that the contractor you spoke to doesn't want to deal with it or he has his own predijuces.

So find someone in your area who has done solar heating installations and knows the state of the art well. I think it's important to find someone local because they will know what works best there.

It can get quite cold there (yes?) and if done imperfectly these systems can freeze and dammage themselves, or actually drain heat from the home to the outside - perhaps the Contractor you spoke to had a bad experiance trying to install or fix a system that was not appropreate to your location.

It also could be that you biggest savings would come from upgrading your furnace, better insulating your home, upgrading your windows or all of these. You need someone who can look at the whole energy picture for you.

Having said all that - it is true that you can put solar collectors on your roof that will heat water (or usually anti-freeze) and store this hot water in a tank and this heat can be used to heat your base board heaters. The problem for household heat is you typically need the most heat inside when the least is available from the sun (cold coudy days). So you will still need a furnace but for many cool sunny days you might be able to get heat from the roof, maybe enough to not need the furnace. You might also look into heating your hot water - after all you will still take hot showers in the summer time when there would be pleanty of sunshine.

Good Luck,
Frank

[Joe Dozzo]

Thanks Frank.

The fellow who says it can be done is a COSEIA member, comes highly recommended and I'm definitely leaning this direction.

Paul, you were right! I quoted KH, not therms! Table below is therms and avg temp.


.........Therms Avg Temp
10-Dec-04 262 34
13-Jan-05 281 35
13-Feb-05 267 38
14-Mar-05 221 41
12-Apr-05 196 49
11-May-05 93 56
11-Jun-05 45 65
12-Jul-05 15 77
11-Aug-05 21 74
10-Sep-05 15 70
11-Oct-05 115 55
11-Nov-05 145 47
10-Dec-05 330 32
13-Jan-06 263 40
13-Feb-06 250 34
14-Mar-06 226 39
12-Apr-06 109 53
11-May-06 62 60
11-Jun-06 24 72
12-Jul-06 14 77
11-Aug-06 12 77
10-Sep-06 65 62
11-Oct-06 98 53
11-Nov-06 184 45
15-Dec-06 330 32
14-Jan-07 262 23
10-Feb-07 296 27
12-Mar-07 157 44
11-Apr-07 59 54
10-May-07 59 54
10-Jun-07 19 58

[Kricnit Not]

Checkout this website.

http://www.builditsolar.com/

This is run by Gary Reysa and he has done some very innovative things with passive and closed loop solar heating. He has an article just published in Mother Earth News on a solar shed that is connected by closed loop water lines to the house to provide home heat. He also has a shop heated by a passive system with no fans or pumps that provides limited (daylight) heating for the shop. He lives in Minnesota or Montana or something way north, so these systems do work in cold climates. Contractors are unwilling to tackle anything outside there area of expertise and your received response is typical. Gary is very knowledgeable and is easy to talk to. Drop him an e-mail after you review his systems and I'm sure he can give you some pointers.

[Rob Beckers]

Ditto on Gary and the Build-it-Solar Web site!
By the way, Gary is a member of this forum. You can send him a private message if there are questions and such.

-RoB-

[Joe Dozzo]

Many thanks. Yes, I did exchange a couple of e-mails with Gary before going ahead with the install.

My solar system is now installed and integrated with the existing gas furnace / baseboard heat. Works great!

Work should be finishing today on the 7kw PV system today.

A tad expensive, but I'm really looking forward to living greener and those low / no utility bills!

[Rob Beckers]

Wow Joe! That's quite something!
Pictures please!