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> In theory, naval propulsion is more amenable to electrification than aviation, but that'll be tricky to do economically; that is another area that petroleum could have a long useful life in.

Over the last couple years / decades, ships went slower and slower on average as to save fuel (fuel became more expensive as well as environmental regulation on how much a ship may emit, which correlates to fuel intake).

So some people in the naval industry propose going back to using wind power, either via traditional sailing or more elaborate schemes (via electricity generation as an intermediary).

> So some people in the naval industry propose going back to using wind power, either via traditional sailing or more elaborate schemes (via electricity generation as an intermediary).

I've seen proposals to use wind power as an auxiliary source. I have yet to see serious proposals to convert to solely wind power.

I think as battery technology keeps getting better. Building batteries in the shape of 40 foot or 20 foot shipping containers would be the way to go. Container ships can then replace battery containers on every port call just like they do the shipping containers. As worldwide we already have networks for the movement and storage of these containers the cost of implementing this system would not be very high apart from the charging stations for the containers but that would be another source for revenue for the ports.

Here's a real engineering youtube video about this!

https://www.youtube.com/watch?v=WWiX2edcBoA

Couldn't you use the rocking of the boat as a means to generate electricity? Seems maybe easier than wind, which I can only imagine as putting some type of turbine on the deck, except in calm seas where you would need to make sure you had enough battery capacity.

> In theory, naval propulsion is more amenable to electrification than aviation, but that'll be tricky to do economically

Unless batteries get a lot lighter, ships are more likely to be powered by liquid hydrogen or ammonia, which are relatively straightforward to produce from renewable energy.

If there is one transport that doesn't care about weight, it's ships. The real problem is cost.

There's two sides to it. For peak loads and shorter routes measured in minutes or hours with easy charging possibilities batteries have been coming for 5-7 years now. The issue is charging since no regen is possible except load smoothing due to operating current engines at a higher thermal efficiency. It's an industry that only looks at cost and barely makes money, efficiency and low-cost workers has been the name of the game for decades.

The hard thing is the sustained loads over weeks. It's not like a car where it gets rolling and then keeps rolling with some air resistance, you need to constantly force yourself through the water, even though it is efficient on a per ton basis.

Consumption on larger vessels can be 150-300 tons per day, say 40 MJ/kg of energy content. Say you only need 50% due to earlier thermal efficiency losses. For a 3 week range from China to the US west coast you still need 30 GWh, or 300 000 Tesla 100 kWh batteries. Which is actually quite similar to the battery capacity of all Teslas delivered in a year. Using 246 Wh/kg we get that the ship needs about 120 000 tons of batteries. A 400m container ship has 140 000 tons of usable capacity, i.e. just the steel excluding all cargo and provision, so it really doesn't add up yet. Need a magnitude improvement before it can start making sense, and this is a calculation without even margins or considering for example China to US East Coast.

It's just incredible how energy dense fossil fuels are. Shipping and aviation will probably end up as the last industries to go green, because they actually use the energy density.

For short haul (think ferries) the same calculations will make electric ships feasible when distance travelled is 1 or 2 order of magnitude less. Such ships already exist.

https://www.bbc.com/news/business-50233206

Yep, that is feasible today. Coastal ferries and routes counted in hours.

Here's a larger ferry connecting Sweden and Denmark that was converted to hybrid with the goal to not use any diesels in regular service. Has 4 160 kWh battery capacity, one trip takes 20 minutes and uses 1 175 kWh.

https://www.youtube.com/watch?v=UyWcY4bTdl8

A company specializing in it is https://corvusenergy.com/

This is very interesting, and if those numbers are right, straight up batteries do not appear very practical for that route. but lets consider that one does not have to complete the longest journey in the world on a single battery charge.

Any of the pacific islands could be built out with infrastructure to recharge them - afterall, sea-based wind turbines are one of the cheapest sources of power, while ontermittent, they are perfect for charging. You coupd even place something akin to an oil platform, but for charging ships.

However maybe something like hydrogen makes more sense.

Agree, except for I think natural gas for homes (cooling and heating) should be phased out sooner. Letting gas companies build new pipe infrastructure to new homes in warmer climates where induction cooking and heat pumps will do the job just fine is crazy. They are an easy, painless way to reduce carbon emissions and much cheaper for society now. Also likely cheaper for the home owner of the future as gas prices get more expensive.

San Jose, CA is phasing out gas in new homes.

I hope coal burning goes away; but that will have a pretty outsized impact on my country (Australia), and the fact that we don’t tax the mining companies enough means our government could end up lacking the means to invest in things to help us transition away from being a mining focused country. It worries me.

Australia will probably end 2020 as the largest natural gas exporter in the world. It's also a country that is very well positioned to take advantage of renewables and export energy via lithium, ammonia, aluminium, hydrogen, electricity (See the sun cable project to Singapore)

This _more_ than makes up for the coal industry

> Tesla has shown quite readily that batteries are probably better than peaker plants for most cases.

Where and how it shown that?

Australia and California.

Does plastic production necessarily emit co2?

> Does plastic production necessarily emit co2?

I don't think so. But it currently uses petroleum/natural gas as feedstock.

Energy is required to produce anything, thus consuming and producing CO2.

Well that energy could be from renewable — we can continue the plastic age into the zero carbon emission age.

So I don’t think that is actually a problem wrt climate change. Then it is more comparable to other mined minerals.