New House Thermal

On Mon, 26 Jun 2017 07:21:39 -0700, 6PK wrote:

On Monday, June 26, 2017 at 1:23:32 AM UTC-7,
wrote:
The Treasure Coast Soaring Club will soon have a new house thermal.
Florida Power And Light is in the process of building a 400 acre solar
power plant within 3/4 mile from our airport. Heat from this type of
farm should make for a great house thermal. Anyone out there with
experience flying over solar farms? Thanks, Bob

One would think it should but it's hit and miss like most spots that
should or could.....:-)

Surely that depends on the overall reflectivity of the solar farm
averaged over its area and over all wavelengths: if its less reflective
than the surrounding area then it will be warmer. But that is only when
its not generating. If the system is generating and exporting electricity
that reduces the energy available for warming the system, so its average
temperature should be reduced as a result.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

On Monday, June 26, 2017 at 4:23:32 AM UTC-4, wrote:
The Treasure Coast Soaring Club will soon have a new house thermal. Florida Power And Light is in the process of building a 400 acre solar power plant within 3/4 mile from our airport. Heat from this type of farm should make for a great house thermal. Anyone out there with experience flying over solar farms? Thanks, Bob

PVT solar panels produce electricity and heat at the same time. It would be very unusual that a 400 acre PVT facility would not produce a constant boomer during solar absorption.

Sorry to disappoint, but I have a glider in South Africa and fly regularly over the Letsatsi solar park which is a 247 acre solar farm north of Bloemfontein SA (on the Dealsville Road). It was built 3 years ago but really doesn't contribute much to thermal activity in the area.

What I have found does work (both in SA and around the world) are the big metal grain silos found on most large farms which (especially when full) get very hot and seem to consistently focus thermals either right over or just downwind of them. That's where I want to be when I am low and scratching.

ROY

On Monday, June 26, 2017 at 4:23:32 AM UTC-4, wrote:
The Treasure Coast Soaring Club will soon have a new house thermal. Florida Power And Light is in the process of building a 400 acre solar power plant within 3/4 mile from our airport. Heat from this type of farm should make for a great house thermal. Anyone out there with experience flying over solar farms? Thanks, Bob

lets make this somewhat simple, the temp of the solar panes on top of the hangar today was in excess of 115 degrees F. I measured the temp reading with a heat gun. The panels number about 16, and the output is a max 8kw. I don't have the output capacity of this project, but I would guess that 100 acres of solar farm could produce 20 MW therefore 400 acres would be 80MW. I would think that if those panels produced the same amount of heat as the ones on the hangar roof and heat travels up, I would assume that we would get some thermal activity from the project.

How did the temperature of the roof surrounding the PV panels compare?

On 6/26/2017 6:43 PM, wrote:
On Monday, June 26, 2017 at 4:23:32 AM UTC-4, wrote:
The Treasure Coast Soaring Club will soon have a new house thermal. Florida Power And Light is in the process of building a 400 acre solar power plant within 3/4 mile from our airport. Heat from this type of farm should make for a great house thermal. Anyone out there with experience flying over solar farms? Thanks, Bob
lets make this somewhat simple, the temp of the solar panes on top of the hangar today was in excess of 115 degrees F. I measured the temp reading with a heat gun. The panels number about 16, and the output is a max 8kw. I don't have the output capacity of this project, but I would guess that 100 acres of solar farm could produce 20 MW therefore 400 acres would be 80MW. I would think that if those panels produced the same amount of heat as the ones on the hangar roof and heat travels up, I would assume that we would get some thermal activity from the project.

--
Dan, 5J

On Wednesday, June 28, 2017 at 11:56:15 AM UTC-4, Dan Marotta wrote:
How did the temperature of the roof surrounding the PV panels compare?

On 6/26/2017 6:43 PM, wrote:
On Monday, June 26, 2017 at 4:23:32 AM UTC-4, wrote:
The Treasure Coast Soaring Club will soon have a new house thermal. Florida Power And Light is in the process of building a 400 acre solar power plant within 3/4 mile from our airport. Heat from this type of farm should make for a great house thermal. Anyone out there with experience flying over solar farms? Thanks, Bob
lets make this somewhat simple, the temp of the solar panes on top of the hangar today was in excess of 115 degrees F. I measured the temp reading with a heat gun. The panels number about 16, and the output is a max 8kw. I don't have the output capacity of this project, but I would guess that 100 acres of solar farm could produce 20 MW therefore 400 acres would be 80MW.. I would think that if those panels produced the same amount of heat as the ones on the hangar roof and heat travels up, I would assume that we would get some thermal activity from the project.

--
Dan, 5J

Good question Dan. The roof is white and was about 12-15 degrees cooler than the solar panels. Also just west of the 400 acre solar project FPL is building another solar plant exactly the same size. That would be 800 total acres of panels within 2 miles of our strip. will be interesting to see what difference it makes. These farms are to be finished by September, unless a hurricane strows them all the way to Nebraska.

If you want a house thermal, you want a refinery. Chicago glider club has two of them within 5 miles, and there are a lot of days in fall when cross country soaring involves a "refinery tour." Also some 7 knot thermals when nothing else is going up more than 3. Of course, if you arrive low and counting on it, you will meet the bubble theory of thermal formation first hand. It was interesting when it was shut down for a few months. You'd think sun hitting the concrete was most of it, and there was a thermal there, but the operation of the refinery made a big difference. Point your wing at the flame in the smokestack...

John Cochrane.

Adding on to Bob's thoughts, at the New Hibiscus Airpark in Vero Beach, FL, we already have three consistent thermal generators right next to the airport: a CVS distribution center just northwest, an outlet mall just east, and the Quad Lakes development just to the southwest. All are within a half mile of the pattern. Add that to the rotation of plowed fields to the west and we have a pretty nice setup here.

Adding these solar farms could significantly increase our house thermals and provide some nice, close to home, final glide thermals for those coming back from XCs. Time will tell...

Paul A.

On Wednesday, June 28, 2017 at 11:56:15 AM UTC-4, Dan Marotta wrote:
How did the temperature of the roof surrounding the PV panels compare?


--
Dan, 5J
On 6/28/2017 11:36 AM, wrote:

The roof is white and was about 12-15 degrees cooler than the solar panels.
During my formative years in soaring, I learned (rightly or wrongly)
that temperature differentials across a surface, e.g., the boundaries
between forests and open spaces, dirt and rocks, etc., are good areas to
look for thermals. That idea has worked for me for a long time. Maybe
you'll find something there after all. Please keep us informed.
--
Dan, 5J

Just got off the roof, where I measured my installation with an IR thermometer. Believe that's what Bob meant by heat gun.

Exposed roof: 135 to 140F, 57 to 60C
Shaded roof: 100F, 38C.
PV panels: 120F, 49C

Jim


On Wednesday, June 28, 2017 at 8:56:15 AM UTC-7, Dan Marotta wrote:
How did the temperature of the roof surrounding the PV panels compare?
Dan, 5J