I would disagree with your logic. Hydrogen has massive advantages over lithium as a storage medium, even if the release efficiency is not as good. Where hydrogen remains limited is the energy input needed to create the hydrogen in the first place. Round trip efficiency is difficult to raise above about 40%, where a lithium EV will be over 90%.
The Guardian article linked to an article featuring a graphic, that looking at it a second time, is a bit misleading:
The graphic with its arrow thicknesses suggests there is a huge energy loss from tank to wheel compared to EV when the comparison is between 94-77 = 17% vs 68-33 = 35%. Sure, a sizeable loss over EV but not as bad as I thought.
Iām still not quite understanding, with that 35% loss just from tank to wheel, on top of the low volumetric energy density at ambient temperatures of Hydrogen, how it realistically compares to electric even completely discounting the well to tank energy (in)efficiencies for either fuel. Is it possible to make serious gains by compression?
No, because compression affects volume, this is not a volume problem. Just think in terms of energy units. Converting energy to hydrogen uses about 30% of the energy. Converting it back a little less, but call it 30% again. If we started with 100 units, the Round Trip Efficiency is 49%. (100-30)*0.7. So in energy units we are getting under half delivered to the wheel. Some systems will be slightly better than those numbers, but not much. With lithium ion, over 90% of the electricity will be delivered to the wheel, so to speak.
The ambient temperature point is basically irrelevant. Hydrogen vehicles use pressurized tanks.
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Hey, it worked for footy, why not climate change?
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Another planet saving vegan family out to save the world, this time round in Perth.
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I donāt see what that has to do with climate control?
Seems a reasonable request to me, hardly entitled or at all threatening or obnoxious. No need for escalation. The world is mad!
sounds a bit fabricated if you ask meā¦
somewhere that story ends with;
āthey didnt have a comeback for my comment and then everyone else all cheered for meā
Actually I donāt know where to put this, in the end chose here because most Vegans I know are in it largely for the climate concerns amongst other things like health etcā¦
And its also possible its fabricated but am not surprised if it is not because there are simply such people nowadays, thankfully still in the minority.
Not sure how that is possible as matured systems support increasing (and attractiveness of) ignorance.
Well it certainly isnāt for the food. Mostly what Iām seeing marketed as Vegan is massively over-processed meat and dairy substitutes where it often isnāt clear exactly what it is made of: the phrase āplant basedā is often used but frequently the base foodstuff isnāt from plants.
There is much to be said for a vegetarian diet, we probably have that on more days than not, but Vegan appears to be a catch-all term for the food processing industry.
From a climate perspective, not all food production is equal, whether it involves animals or not. It would be worth having some indication as to what the true impact is.
Thatās pretty much why Iāve retreated from it a little. Iām trying hard to eat more foods that are as nature intended and not stuff just because itās plant based.
This makes for sobering reading:
It includes this graph which I have seen discussed elsewhere of average global sea temperatures.Now literally off the scale:
We are beginning to see some direct signs of destabilization of North American wind patterns. Prevailing wind direction is from west to east, but that used to be overwhelmingly so. The incidence of a counter-cycle has soared, a counterclockwise rotating air current roughly originating in the Gulf of St. Lawrence. That has been in operation for over half of June, we are in our second occurrence. It was positively bizarre last week when one started during our air quality episode. One of the larger fires was less than 200km to the northwest, in 24 hours we went from the worst observed air quality in the world to almost pure air. Meanwhile, that rotating air current was carrying those particles all the way to New York City.
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UK has been in that reverse pattern for at least a month probably 6 weeks now.
I bought a new kite surfing kite some 7-8 weeks ago. Tradition has it that a wind curse will strike and you can rule out using said new kit for a month. Itās still in the wrapper.
UK is predominantly SW which works for my local beach. UK has been locked in a NE / E wind pattern for the last 6 weeks Iād say. Itās given us the highest June temps ever and wouldnāt surprise me if it was the driest May on record as well.
We do normally get a short spell of this āreversedā wind in May, lasting say 2 weeks. Another one in say October. This is nuts.
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Direct relation with ocean temperature.
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speaking ofā¦our planet has been in a global warming stage since the (last?) ice age and they still donāt know what caused itā¦
No question that humanityās development since the industrial revolution is accellerating the warming of the planet, but to what degree of this warming pattern is actually at fault to us?
Study solves long-standing mystery of what may have triggered ice age | University of Arizona News.
That study doesnāt really speak to that question though. It is answering how can there be different local effects in the context of a given temperature (more ice forming in this specific region than youād expect for a given local temperature).
As to why weāre warming the way we are know there are many known causes that have contributed to climate changes in the past. All the known mechanisms have been ruled as explanations for the current cycle, with man made change being identified as being responsible for the overwhelming majority. There are debates around the margins but it is really not contentious to say there is incredibly strong certainty that the result of entirely man made causes.
again, not to argue that mankindās development in the last 200 years has contributed to global warmingā¦ but what about the other 9800 years since the ice age when the glaciers reached down to the Canada/US border?
I think I directly addressed that in my response, no?
You may not believe it, or understand how theyāve come to that determination, but the scientific community have looked at the question and speak overwhelmingly with one voice on the answer and with very high confidence.
In short, the existence of other reasons for warming being present in the planetās past does not mean they are part of the current cycle
so considering the earthās own obliquity changes (on 20,000yr cycles) and the aligning of that timing with the Milankovitch cycle (41,000yr cycles) which help to explain why weāre currently halfway between ice ages, donāt you think itās a bit narrow-minded to take that stance? considering that some of these changes that are happening would have happened anyways? Just now on a more accelerated timeline?
Again, 10,000yrs ago my home was under 3-4km of iceā¦ the sea level was 120m lower than it is now.