The climate change debate continues.

[spacesailor]

The poms will have to keep using plastic bags, if the wood IS being burnt for power generation. 

Those Old paper bags were useless , And did we cheer when the versatile plastic bag came onto the scene. 

Will we have to forgo our great platic ropes, so much better than natural fibre ropes .

spacesailor

[Jerry_Atrick]

Farmers over here have been putting in solar farms because the return they get from them can be better than traditional agrculture. There is a solar farm not too far from me that seems fairly tightly packed with panels (though I wouldn't know), and the grass underneath seems to grow OK,. despite lack of direct sunlight. I have seen sheep grazing in a solar farm with areas fdenced off, so they don't totally destroy the utility of other uses of the land, but I imagine it would be far less productive.

 

As for the aaesthetic blight on the landscape? When you consider the alternative, what would you prefer? Of course, the other alternative is to "simply" use less forms of energy.

[Yenn]

Solar farms are placed close to existing transmission infrastructure to make it cheaper, plus nobody cares about the take over of good agricultural land. The pumping of water to produce electricity from a dam when sunlight fails would need solar farms near the pumping site, but I doubt that would happen as the bureaucrats would not like it.

[Old Koreelah]

On 03/10/2022 at 11:06 AM, old man emu said:

It is ironic that what is touted as the saviour of the atmospheric environment - solar power generation - 

 

...those arrays are a blight to the visible landscape and remove agricultural land from production.

Often true, but sensible design (rare in Oz) can overcome this.

Plenty of solar farms graze sheep, and report only a small drop in yield. The panels give plenty of shade, important to livestock.

 

India is killing two birds with stone: covering irrigation canals with solar panels- no land lost, evaporation losses greatly reduced.

[onetrack]

Quote

India is killing two birds with stone: covering irrigation canals with solar panels- no land lost, evaporation losses greatly reduced.

Not quite as simple as it sounds, Old K. In W.A., researchers from the UWA carried out water loss checks from agricultural dams, looking for ways to reduce water losses from evaporation.

To the researchers surprise, it was found a very large percentage of the evaporation losses from agricultural dams was via steady, warm to hot winds, at night.

The percentage of the water losses at night were around 35% to 45% of total water evaporation losses. So keeping the warm winds from accessing the surface of the open water, is just as important as keeping the suns rays from hitting it.

 

The Indians would be well advised to structure the position of their solar panels so that they acted as a wind barrier to the canal water, as well as a sun barrier.

 

http://www.insidecotton.com/jspui/bitstream/1/1927/1/er061198.pdf

[old man emu]

6 hours ago, onetrack said:

it was found a very large percentage of the evaporation losses from agricultural dams was via steady, warm to hot winds, at night.

That stands to reason. Consider a parcel of air, say a cube with sides of 1 metre. That's big enough to imagine. Within that cubic metre you have the three main gases - nitrogen, oxygen and carbon dioxide. The next major gas is water. The amount of gaseous water we measure as humidity. If the air is warm to hot, then you would expect the parcel of air to be able to hold more gaseous water than cooler air. If the air has low humidity before it reaches the water source, then it can accept more as it passes over the water. 

[spacesailor]

But !.

No-one accept.s , the world Is returning to a tempreture that was the Normal in prehistoric Dynasaur,s days .Hot & wet with huge plant growth .

spacesailor

[old man emu]

4 hours ago, spacesailor said:

.Hot & wet with huge plant growth .

My Buffalo grass is beginning to grow. I'll need a big mower because buffalo grow tall.

[Yenn]

I have seen those Indian canals and they run from the foothills of the Himalaya for hundreds of km. shading them with solar panels would delay the warming of that ice melt water and therefore reduce evaporation loss.

Here in Central Qld in summer the loss from my dam is more in daytime than at night. Maybe that is because we have more wind in the daytime and the night time wind is a cooler land breeze.

[kgwilson]

There is also more sunshine during the day than at night.

 

As for grazing animals and growing crops on a solar farm, studies to date have shown little reduction of animal density but a lot of benefits such as keeping the grass and weed growth down so as not to obscure the panels, provide shade for the animals and in a study near Parkes the sheep have produced much improve wool quality.

 

https://www.abc.net.au/news/rural/2022-05-30/solar-farm-grazing-sheep-agriculture-renewable-energy-review/101097364#:~:text=Solar farm trial shows improved fleece on merino sheep grazed under panels,-ABC Rural&text=Sheep grazing under solar panels,projects began%2C according to growers.

[spacesailor]

But 

Why do they put the panels so low .

If twice the hight, what difference does it make to the panel output ?.

I saw one field of panels less than a metre above the grass,  no sheep there to keep that grass down .

( no I didn,t measure them ).

spacesailor

[Marty_d]

Cheaper to build them low.  Less engineering and structural steel required.

[old man emu]

3 minutes ago, Marty_d said:

Cheaper to build them low.  Less engineering and structural steel required.

`Typical short term thinking. Put them 1200 mm high and sheep can get under them to do the mowing. Steel is cheap if the price is offset by wool/meat production over the life of the steel frame. 

 

How long would those panels last, anyway? 

[Marty_d]

I'm not saying I agree with it, OME, just giving a possible reason they did it that way.

[onetrack]

Good quality solar panels have a lifespan of at least 20 years. However, they suffer performance decline at a rate of about 3% a year, on average - so after 10 years, they are 30% down on their nameplate capacity. Even the very best quality panels still suffer about 2% performance decline annually. So, best case scenario, is that a 20 yr old top quality panel has lost 40% of its power generating ability.

[red750]

43 minutes ago, Marty_d said:

Cheaper to build them low.  Less engineering and structural steel required.

And easier to clean the dust off them.

[spacesailor]

Those huge water canons that farmers use , will soon clean the dirt off the panels, when watering their  'LAWN ' .LoL

spacesailor

[Jerry_Atrick]

I was going to say, "can Aus afford to waste water with those cannons in a drought?" But I have just seen the forecast.. not looking great for land lovers. 

 

Anyway - how low do you fellas  build them? The start about about 1m and rise to, I guess, 1.4m off the ground.. Sheep fit under them nicely. Don't want cows in there, anyway - they are far more destructive than sheep (although steel poles should be somewhat resistant).

[old man emu]

3 hours ago, Jerry_Atrick said:

Don't want cows in there, anyway - they are far more destructive than sheep

[nomadpete]

No, bull......

 

No bull !

 

Expect a rebuke from the grammar police.

[Marty_d]

12 hours ago, old man emu said:

It really happened??  Or was it photoshopped...

 

Either way, if you're going to post photographs of common metaphors, can't wait til you get to the one about nuns and dryness.

[nomadpete]

2 minutes ago, Marty_d said:

nuns and dryness.

Is that the drought in central australia?

[Marty_d]

2 minutes ago, nomadpete said:

Is that the drought in central australia?

I reckon a few farmers would use that expression around there.

[kgwilson]

Drizabone? Nah use that when its wet. Drizanuns err Habit? Nah same use. 2019 would have been the year for that expression.

[Marty_d]

Don't know if anyone watches "The Boys" but there's a great scene with Karl Urban who plays a cockney tough guy, and he forgets he's talking to a kid.

"Mate, I'm as dry as a nun's..." and then he stops.  

The kid just looks at him and says "You were going to say 'vagina', weren't you!"