Tuesday, November 26, 2019

Alternative history: solar PV development in World War 2

I'm partly inclined to a chaos theory of history where lots of outcomes are contingent. Alternative history (wiki pedantically insists on "counterfactual history") can explore what could have been.

So, could solar PV have gone through development boost during World War 2? Solar panels were first deployed in 1884 and researched intermittently afterwards. What if someone with sufficient political power during the war got a research program together on solar power for military purposes - could they have done anything with it?

My answer is a limited yes. These would've been selenium cells, not the silicon chips discovered in the 1950s. At 1% efficiency, that's good enough to recharge batteries for radios, lights, maybe other tools (weather instruments?). Isolated outposts in the Pacific and commando operations in Southeast Asia and Europe could've benefited from this.

The effect on the war likely would've been a modest benefit for whichever side used them (Japan could've benefited as much as the Allies) but unlikely to be a gamechanger. The only exception might be in the Pacific where the outcome of naval battles seem to rely so much on chance, so that slightly better information about enemy forces could've affected individual battle outcomes. Still, in the long run the Axis was doomed pretty much regardless and the question is only how fast they would lose.

For solar panels and climate change, the effect would be slightly better. The first practical use of solar PV was on spacecraft in the early 1960s, and the second about 5-10 years later was on isolated outposts like oil rigs and navigation buoys. That second use could've been discovered in the 1940s instead of 25 years later. By itself that does little to reduce emissions, but it might have accelerated the declining cost curve for solar power - not by 25 years, but by some amount.

So that's a might've been. And even in the real history, World War 2 did have an effect on solar PV because it accelerated rocket technology and eventual satellite development, where PV was valuable regardless of price. A small benefit at a horrendous cost in life.

Two other possibilities - first, I don't know the power requirements of World War 2 radars but I imagine they could be powered by batteries. That means outposts could be monitoring ship movement and weather at night, making them much more effective if solar PV kept them charged up. Radar wasn't totally a secret during the war btw, just the most advanced forms, so the Allies could've deployed this without risking their advantage. I'd guess this would have somewhat more effect on the war, but little additional effect on solar PV implementation.

A second, more out-there alternative history imagines that the electric vehicles of the 1910s and 1920s continued to be developed up to World War 2. Having military vehicles powered by solar PV could've had strong effects on the war. Patton's breakout from Normandy was eventually stopped by a lack of fuel, not by the Germans. Interesting to imagine how it could've gone if after a day of recharge, even some of the units could keep pushing forward. It's also hard to imagine recharging a tank on solar panels, though, but even if you only have electric bikes and motorcycles, that could be useful during the war, and maybe help keep electric vehicles in production afterwards.

Some interesting timelines, but we have to deal with the one we've got instead, and make the best use of it.


Canman said...

I think solar would'f been pretty much useless in WW2 due to low energy density. It's kind of hard to hide acres and acres of solar panels for charging your electric jeeps and such. Wind powered ships were displaced by higher energy concentrated coal and oil. The war was finally ended with the highest concentration fuel of all at Hiroshima and Nagasaki.

The lead acid battery did find a unique use -- to power quiet electric motors for submarines. I don't think there's much room left for chemical batteries to improve. The chemistry is pretty well understood, or maybe the rabbett knows something we don't, since he is a chem prof. There may be some new conceptual storage improvement. My candidate is carbon nano-tube flywheels.

David B. Benson said...

It is a myth that the A-bomb had any direct effect in causing the Japanese government to surrender. The precipitate cause was the Soviet violation of their non-aggression pact to invade Manchuria.

See "Japan's Longest Day".

Dan said...

The display for a WWII radar was basically an oscilloscope with long-persistence phosphors. It is possible to make such scopes with relatively low power requirements; battery powered scopes certainly existed in the 50's. The main power draw for an active radar system is the signal transmitter, with the range and resolution depending directly on the transmitter power. Passive radar is possible, and according to WP the Germans had a passive radar system (Klein Heidelberg Parasit) that used the British Chain Home system as its signal source. I believe a battery powered passive radar for forward outposts would have been feasible with WWII technology, but I'd also guess that charging it with solar cells would have required an impractical array size, and the position resolution for WWII passive radar had limited utility.

Canman said...

Was it a myth that the A-bombs caused Japan to surrender? Read more than one book on any historical event and you will most likely get more than one interpretation, often vastly different. We do have one definite piece of data -- Japan surrendered shortly after the two A-bombs.

Phil said...

(Fixing a serious typo)
@Japan's Longest Day. I've got a copy on my desk now.

JLD mostly deals with the messy aftermath of the decision to surrender. Revolts by the military and others, murders and attempted murders, suicides, assorted politics and such. It wasn't clear until the very end that Japan would actually surrender.

I don't see how anyone can come to the conclusion that the Soviet invasion of Manchuria was the sole reason for the surrender, based on this book, or any other source or any realistic reasoning.

The decision to surrender was perhaps made by the Emperor on August on August 8th (JLD page 22) before the Russian invasion. The Emperor's command: "in view of the 'new type' of weapon that had been used, Japan was now powerless to continue the war and must make every effort to terminate the war with the least possible delay."

Or perhaps was made by the Cabinet on August 9th, or perhaps early AM on August 10th. At that time, the Russian invasion was thought to be minor, the "scale of these attacks is not large".

The most powerful person in the cabinet, General Anami had predicted in June that the Russians "would attack Japan just as the Americans were preparing to land their forces on our islands." General Anami was counting on the Russian attack to force the Americans to offer more advantageous terms. Page 19. The Russian attack was expected, almost hoped for, and didn't change calculations.

The atomic bomb was unexpected.

The USA was dropped 46k tons of conventional explosives on Japan in July. 53k tons in August was planned. 80k tons per month by the end of the year. per month. The two 10k to 15kt atomic bombs were a small fraction of the destruction caused by 157k+ tons of conventional bombs dropped on Japan over the war. Small bombs are more efficient than large bombs on unarmored targets.

Another, much older weapon of war. Starvation. Most of urban Japan was out of food in August 1945. Continued war, or a peace similar to the "four conditions", would have lead to the death by starvation of 10's of millions of people. No occupation, no ex-President Hoover speech to Congress, no American food aid. Even with that, rations were 775 calories per day for a full six months in 1946. And were often not delivered. Just a week more of continued war would have meant the planned bombing of the sole rail link between Northern Japan, where there was excess food, and Southern Japan. Even with American food aid, widespread starvation could not have been adverted without this rail link.

Starvation doesn't get the headlines.



'It's also hard to imagine recharging a tank on solar panels'

A new summer house on MV sports a solar roof that can recharge a visiting Tesla in the time it takes to have lunch.

If you had a 500 HP electric tank, his 19 kilowatt roof could put roughly 100 miles worth of charge into it on a long June day

David B. Benson said...

According to
it was the Soviet invasion which caused the surrender of the Japanese. This view is contentious.

Phil said...

"This view is contentious."

Almost like the view that increasing CO2 is warming the climate is contentious. But not quite.

Was there someone that was convinced by the Soviet invasion to accept the surrender? Yes, at least one, but none of the major figures.

The Emperor was pro-war until the defeat on Okinawa. He then switched to a vague hope that Russia could get a better deal to end the war than unconditional surrender. This seemed to have no urgency, as the Japanese ambassador to Russia couldn't get a statement of acceptable terms. The first urgency came on August 8, before the Soviet invasion or declaration of war.

Not until August 14 is there any mention of the Soviet invasion in any of the Emperor's recorded statements. Seems to be the Emperor's fourth reason for the surrender, after the a-bomb, the collapse of domestic moral, incomplete preparations for the impending American invasion, and then the Russian invasion.

Of these reasons, only the a-bomb was given in the official speech that ordered the end of the war.

Yet the Emperor's decision wasn't sufficient. Read Japan's Longest Day for more details.

The head of the Army, General Korechika Anami, was not convinced by Hiroshima, as he was "convinced that the Americans had only one bomb, after all." The Nagasaki bombing (and perhaps other events) changed his statements to the Americans would soon be dropping three a-bombs per day. He had long expected and hoped for a Russian invasion to put pressure on the Americans to improve their terms.

As the head of the Army, General Anami could have prevented or delayed the surrender. He didn't. He was under pressure from pro-war military officers to resign, so someone else could prevent or delay the surrender, and he didn't. He was under pressure to allow the army to take control of the palace and take the Emperor away.

As Wikipedia says "His refusal to support any action against the Imperial decision was a key point in the failure of the Kyūjō incident, an attempted military coup d'état by junior officers to prevent the surrender announcement from being broadcast."


Who was convinced by the Russian invasion? The rest of the Cabinet?
Not PM Baron Kantarō Suzuki. Would accept "one condition" surrender before the a-bomb. Suzuki was opposed to Japan's war with the United States, before and throughout World War II.
Not Shigenori Tōgō. Likewise. Had been forced out of the Cabinet due to his opposition to the war, and returned in the summer of 1945.
Not Admiral Mitsumasa Yonai. Loyal to the Emperor. Strong sense of morals. Never charged with war crimes.
Not General Yoshijirō Umezu. Pro war to the end. Signed the surrender document after a personal command from the Emperor.
Not Admiral Soemu Toyoda. Pro war to the end. Acquitted on war crimes charges.

So where might we find someone convinced? The diary of an aide to General Anami records a conversation with an unnamed lower ranking officer of the army that was concerned with the Russian forces invading, and who accepted the surrender agreement for that reason. Perhaps there are more. The vast majority of Japanese officers obeyed the surrender order. At least one was convinced by the Soviet invasion.

I suggest you actually read "Japan's Longest Day" to find out how close the actual surrender was to being prevented. While the Russian invasion wasn't the first cause of the surrender, or even the second or third, it might have be critical. It was a close thing. Perhaps that was General Mori's reason to resist the coup. We can't know, as he was murdered during the coup attempt. As General Anami said when told of his death, "just one more thing to apologize for." His suicide note read: "I—with my death—humbly apologize to the Emperor for the great crime."

Brian said...

Re active radar: I'm still talking from ignorance re power requirements, but simply revealing a large, undifferentiated mass of ships passing through a narrow straight at night could be very valuable information. Maybe that doesn't require prohibitive power or technology too sophisticated to risk having it at outposts.

No idea about what minimum power at the time would be sufficiently useful for weather radar.

Re solar PV-supplied tanks: I'd like to see the numbers crunched by someone more diligent than me. I can't imagine the size of a PV array running at 1% efficiency, as well as the size/weight of lead acid batteries that would be needed to run a tank a good distance. Lighter vehicles that help infantry keep up with the armor might be more feasible.

Phil said...

"These would've been selenium cells, not the silicon chips discovered in the 1950s. "

Silicon solar cell was discovered in the 1930's. Notice silicon solar cell, there was exactly one. The second one was made in the 1950's once Bell Labs figured it out.

Suppose Bell Labs had figured out how to make the second solar cell in 13 days rather than 13 years?

I doubt if it would have much impact on the result. Vacuum tubes are power hungry at best. Only if there were also transistors... and computers and more. Smart bombs and such have large military impact as only a few bombs are need to destroy a target.

Tanks need lots of mass for armor and cannon. Lead acid EV tanks would have been short ranged, at best, and overweight and/or under armored and/or under armed. Not useful. Worse than the Sherman tanks, which were under armored and under armed deathtraps. But quite fast and light weight...

David B. Benson said...

Phil, I read "Japan's Longest Day" many years ago.

David B. Benson said...

Down the slot in the Solomons there were coast watchers on duty. No radar required.

The Germans sometimes used bicycles for infantry mobility.

Bernard J. said...

It's probably worth going back another four or five decades and asking what might have happened if battery-powered vehicles had been given a little more traction against those with internal combustion engines...

Canman said...

The weight of the lead acid batteries of four or five decades ago, probably gave electric vehicles of the time, all the traction they were likely to get.