Rooftop solar system fires 1

[itsmoked]

Apparently it makes a darker disc in the air that birds can more easily recognize.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[MortenA]

Re birds and wind turbines: The Danish ornithologist society estimate that a wind turbine on land on average causes the deat of 4 bird pr. year based on research done in the German Bundesländer Brandenburg (comparabel to Denmark). Cant really say if thats few or many. I guess it will depend on the species killed. Appearent eagles are not scared by wind turbines and sea eagles often gets killed by wind turbines. In Denmark its estimated that wind turbine annually kills 10,000-17,000 birds whereas traffic kills 1,100,000 birds.

--- Best regards, Morten Andersen

 

[itsmoked]

To add to Morten's data, cats kill 2.4 billion birds a year.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[Alistair_Heaton]

Sounds about the same as the stuff we hear in UK.

Aviation wise we hit relatively alot of birds of prey as well because they are not scared of us.

Have sat a few times in a thermal with a bird of prey with it eyeing us. Prey birds high tail it out of there.

This is different to the flocking birds who maximise their individual chances by keeping close together. Aka what sully had to deal with.

We never hit black crows way way to intelligent.

 

[cranky108]

Alligator lizards in the air? Is that what that means?

Power companies also have to keep track the birds that are killed. But building owners don't. Why?
Shiny buildings injor more birds per year.

There is another type of solar that uses mirrors to focus the sun light onto a pipe. But not so high temperatures.

 

[JohnRBaker]

There is another type of solar that uses mirrors to focus the sun light onto a pipe. But not so high temperatures.

That sounds more like a system for producing, or at least preheating, water for a domestic/commercial hot water system. There's a couple of homes near here who have both photovoltaic and what appears to be panels which have what looks like plumbing running to and from them. I've heard of people installing systems like that to heat their swimming pool.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[spsalso]

I took a "solar" class towards the end of the last century. That class was almost completely about using solar for heating, both buildings and water. I don't recall anything about photovoltaic, probably because it was still strikingly expensive to do for a whole building. I had an acquaintance who also took the class and installed solar hot water. As far as I know, it's still working.

My recollection was that one option was to build your own (hot water) "panels" from scratch. I don't think there was much out there commercially.

The class was quite interesting. There was discussion of placement of thermal mass and windows and roof overhang and........


spsalso

 

[SnTMan]

JRB, I beleive cranky108 was referring to the so-called Solar Energy Generating Systems, also located in CA. Generates steam to run turbines. Looks like mostly retired in 2021, replaced with PV.

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[JohnRBaker]

Yes, I once considered doing a solar hot water system, but nothing came of it as that was about the time that we moved from Michigan to SoCal. While we owned our home in Michigan we had to rent when we first got here, and I lost interest, but I've still got a couple of books that I bought back then, 'Solar Heating and Cooling: Engineering, Practical Design, and Economics', by Jan F. Kreider and Frank Kreith, published in 1975, and 'Producing Your Own Power: How to Make Nature's Energy Sources Work for You', by Carol Hupping, published in 1974. While the first book was your pure engineering text, the second one was more of a new age tome published by a company known for books on organic gardening and such.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[cranky108]

I actually have a solar water heating system on my roof. It was there when I purchased the house. It now doesn't work, and I have no documents on how it is supposed to work.
I suspect it needs anti-freeze, but I don't want to climb on the roof to put it in. Besides what type?

 

[Alistair_Heaton]

There must be piping down to some system in the house and a control system. You can usually service them without going on roof.

 

[itsmoked]

Now days the plumbing and freeze issues tend to drive people to PV water heating instead as a 'dry' power cable is much easier to run and solar panels are cheap. You add an electric water heater in front of the existing water heater and it preheats and stores the solar thermally.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[Alistair_Heaton]

The big thing in uk is the mysolar Eddie and zappi products which divert solar hot water and ev charging.

People are also fitting Willis heaters to use with it for filling the full tank.

 

[TugboatEng]

Itsmoked, I don't think there are subsidizes for solar heat, only PV.

The freeze issues are easily managed with a bit or propylene glycol.

The corrosion issues are a bigger problem. They are easily managed but most lack fundamental understanding of corrosion prevention including those that sell the treatment products (there are steps required to prepare a system for protection).

 

[itsmoked]

I don't think there are subsidizes for solar heat, only PV

All the better reason to use PV.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[cranky108]

Actually, the water heater system I have, stores the pre-heated water in an electric hot water tank. Just that the electric element is not connected.
I guess I could use it, and set up some PV to heat the water heating elements.

 

[itsmoked]

More and more people are going that route as no one wants to deal with the plumbing, antifreeze, and heat exchangers and all that. This is making the electrical aspect of water heating get some focus. You can now get elements that are half and half, half line voltages and half DC solar voltages. DC switching hardware is showing up.

You might find this DIY Solar thread I started interesting reading. I'm surprised it's the largest thread on the entire forum by more than 2x if I'm not mistaken.

direct-to-water-heating

Keith Cress
kcress -

http://www.flaminsystems.com

 

[cranky108]

True that typical electric water heater thermostats are not made for DC. But even with a typical 120v inverter, it may not work as expected, as the elements are made for 240V.

 

[Alistair_Heaton]

There are alot of people using these Willis heaters on their water tanks in europe with solar to avoid giving electricity to the grid free.

https://www.stevensonplumbing.co.uk/willis-external-immersion-heater.html

https://heatingpartswarehouse.co.uk/product/willis-external-immersion-heater/

They fit them in parallel to the cold input and the top of the cylinder. And it just cycles the water in the cylinder until the whole thing is at whatever temp you like no pump required.

You can get DC immersion heaters versions and they have a temp safety cut out.

Don't have one personally but everyone seems happy with them, usually linked to an Eddi solar diverter. Some have 2-3 in series, and they kick in and out depending on the solar output.

Some run them direct DC as well just limit the series string voltage so it doesn't bust 230V the current will be self limiting any way to under 12 amps 3 kW immersion max current is 13 amps. And they put them on the buffer cylinder, but you need to have mixer valves on every circuit if you do that.

 

[LionelHutz]

Plumbed right, a solar water heating system can be setup to drain at night and then not require heating loops or anti-freeze.