Urban Heat Sink is perhaps the largest man-made contribution to Global Warming. So cities with lots of black pavement and cement buildings all soaking up the daytime sunshine retain this heat and slowly emit the store heat throughout the night hours. So if you took the temp in NYC in 1860 at noon and again at midnight let’s say it was 100 degrees at noon and 60 at midnight you would have an average of 80 degrees. Now today if you took those reading and had 100 at noon the city would not cool off as quickly or as much as in 1860. So let’s say it is 70 at midnight. This has today’s average temp as 85 degrees, 5 degrees warmer than in 1860. This is essential “Urban Heat Sink”
This same principle applies to whole cities and communities that have been built in the last 50 -80 years in areas that were once open fields, forests, citrus groves, and so on.
So many have asked how much will a field of black solar panels raise the temperature of that field?
From an article in The Conversation:
“While the black surfaces of solar panels absorb most of the sunlight that reaches them, only a fraction (around 15%) of that incoming energy gets converted to electricity. The rest is returned to the environment as heat. The panels are usually much darker than the ground they cover, so a vast expanse of solar cells will absorb a lot of additional energy and emit it as heat, affecting the climate.
If these effects were only local, they might not matter in a sparsely populated and barren desert. But the scale of the installations that would be needed to make a dent in the world’s fossil energy demand would be vast, covering thousands of square kilometers. Heat re-emitted from an area this size will be redistributed by the flow of air in the atmosphere, having regional and even global effects on the climate.”
This question was first asked years ago and not data was available at the time and the answer was, of course, No it doesn’t work that way. The panels absorb the heat etc… However, now that there has been time to study and collect data the answer seems to be leaning more towards well…very little. Which as The Conversation’s article points out a little, multiplied by how many solar panels are going to be needed in the future adds up to a lot.
This doesn’t even bring into account the growing concerns over the chemicals needed to make the panels or being released into our atmosphere like NF3 and how that may be a far more deadly trade-off not even being considered.