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There was a company called Wiferion that was bringing this exact product to market. They were bought by Tesla though and nothing has since come out.

There is another company called Witricity that claims to have a product ready in 2025.

At the extremes one is, as far as our technology allows, irreplaceable as a carbon neutral fuel. That being SAF. The other other viable alternatives even today. Why are you presenting a scenario where both would be needed to be created in equal measures?

So what if they can both come from the same feedstocks? There will be a day we likely don't need diesel in any capacity. We'll need SAF long before that. Why would we divert the valuable carbon neutral feedstocks to something like biodiesel if our goal is carbon neutrality for both?

There is a regional chain of grocery stores in my area that have level 2 and 50Kw level 3 chargers. They give you 1 free hour of level 2 charging per day (per location, I later discovered). At 9.6k charge rate, its not a huge savings, but I almost always use it when I grocery shop and its nice to come out to the car with 5% or 8% charged added.

This is extremely disappointing. Replacing existing purchased government vehicles early is neither fiscally sound nor environmental. The only group that benefits from this is petroleum companies that stand to gain back additional fuel consumption lost to EVs.

Years ago there were few public EV chargers, and even then it was common when I used one that I was the only one there. Today there are many more public EV chargers and and multi-stall chargers, its more rare that I'm the only one charging.

It doesn’t really matter whether you’re producing biodiesel or SAF; it’s a slightly different length of carbon chain coming out of the refinery.

The difference isn't the slight variation in chemical structure of the molecule between the two products, its the drastic difference in the applicable use case of the resulting product, and the economic incentives to produce one vs the other. These are what make the SAF and biodiesel gigantically different product with hugely different economic, climate and geopolitical implications.

No amount of B5, B20 or B100 grades of biodiesel are going to enable carbon neutral air travel where SAF can. However, alternate fuels or methods of ground transportation can offset or replace diesel or biodiesel. With today's technology only a number of small electric prop planes (certainly no commercial jets) can operate with anything close to carbon neutrality without SAF. Commercial aviation is a reality in our world and we can choose to find carbon neutral alternatives or embrace its carbon rich nature and try to make drastic carbon cuts elsewhere. I believe the latter is much less likely than the former. Alternatively we can simply turn a blind eye to our climate and reap the consequences. I'm not ready to throw in the towel and embrace that yet.

The same problem of competing with food is there because that’s where you’re sourcing carbon and hydrogen from.

Even if a portion of input feedstocks that go into producing SAF today are food or competing with food, how are you holding the position that municipal waste, used cooking oil, and agricultural waste are sources of food? I've posted sources that show the alternates available and possibly upcoming that would enable more non-virgin SAF. Are you holding the position that humanity will simply never achieve anything except fossil based fuel for aviation or something else I haven't understood of your position yet?

Further yet, what is the connection you're making a food supply with regard to hydrogen? Are you referring to fertilizer?

First, that is a great link. I don't follow biodiesel efforts very closely and always appreciate the data from a real world execution perspective.

That said, while the article contains a number of criticisms you're pointing out, the article is mostly focused on biodiesel and not necessarily SAF, and even less applicability to California where the majority of North American SAF is produced. The article even called this out with the distinction that biofuels (SAF in this case) from virgin feedstocks doesn't qualify for the Low Carbon Fuel Standards (LCFS) laws in California that make SAF economically viable. Meaning there is far lower incentive to try to produce SAF from virgin feedstocks, which I believe is your primary criticism of SAF.

"Additionally, the Producer’s Tax Credit, coupled with the California LCFS, will heighten the demand for lower carbon-intensity feedstocks like tallow, UCO, and corn oil. Under the LCFS, west-coast market demand is stronger for feedstocks that provide greater carbon-emission reductions than virgin vegetable oils like canola and soybean oil. These policies will continue to pull available global feedstocks into the California renewable diesel market, and boost U.S. import demand for feedstocks that make lower carbon-intensity biofuels that generate additional credits in the California market."

from your provided source

The other point your article highlighted was the bottleneck to using less virgin sources was the need to increase the non-virgin sources of feedstocks. As in, the market is demanding more biofuel from non-virgin feedstock than can supplied. This is important as it goes back to the work identifying and introducing further non-virgin feedstocks that I linked in my other post on this topic here.

Food. Food oils in particular.

While certainly possible technologically, for the main efforts in North America you are incorrect on the use of food (meaning something humans can eat) for SAF.

The largest producer of SAF in the USA is in California (and partially fuels LAX airport, BTW). This operation is using waste from other processes and not food that would otherwise be eaten.

source

That is a very important question. SAF is a name for a bunch of different fuels produced from sustainable sources. I posted a larger reply to the main article that details some of the input feedstocks which answers your question here.

I'll preface this by saying that SAF by itself isn't a silver bullet that solves all problems with carbon use in aviation. It can, however, be an important piece of a larger solution. Additionally, even in isolation without a larger plan it has a net benefit on carbon reduction which is a win in the battle against climate change.

The basic problem is that “sustainable” aviation fuels, if based on biofuels, would substantially compete with food production.

Certainly possibly, but not absolutely.

Virgin feedstocks (the stuff needed to feed in to make SAF) would support your position because the plants grown specifically for harvest to be turned into SAF would displace food crops, or possibly support destruction of other non-agricultrual land to grow net more crops. I agree with you that both of these situations would be a net negative to SAF.

However, virgin feedstocks aren't the only nor even most desired feedstocks for SAF. There are many ways to produce the fuels that fall into the definition of SAF. Things that we would otherwise consider waste streams can be SAF feedstocks such as the following:

source

There are other pathyways being explored too such as the waste water runoff from dairy farms and beer breweries:

"To that end, the Argonne Lab scientists look to using carbon-rich wastewater from dairy farms (and breweries, for other reasons) as feedstock for SAF production. The study author at Argonne, Taemin Kim, said that the energy savings come in two ways. “Both [dairy farms' and breweries'] wastewater streams are rich in organics, and it is carbon-intensive to treat them using traditional wastewater treatment methods. By using our technology, we are not only treating these waste streams, but [also] making low-carbon sustainable fuel for the aviation industry.”"

Source

Unless we as a global society choose to simply eliminate air travel for people and cargo, we have to accept that a better approach to energy used for air travel is needed to meet reality. SAF is an important part of that in my mind.

Yes, I'm one.

Like most things, not one thing will fix a problem. SAF is one piece that measurable makes our situation better. The fact you can possibly fly on a plane today partially with SAF is an amazing achievement and the result of lots of hard work by lots of people trying to make a positive difference.

We have the excess electricity already, but I’m not yet at the legally required amount of solar panels.

At work we are investing in energy storage, both batteries and heat storage and looking for more solutions.

For any but the largest commercial solar/wind providers, batteries and heat storage (or cold storage actually too!) are the best uses of overproduction of electricity. Batteries at your location are 90%+ efficient round trip, meaning for every 1kWh you shove into the battery, even after all the conversion and storage costs, you'll be able to get 900Wh or more out of the battery when you have a use for it. Many PV tied batteries are upwards of 97% efficient even!

Heat storage is another great use, whether in water (to mitigate need for new energy expenditure to heat water for use), or in thermal batteries for space heating. Although the biggest downside to thermal batteries are their size. If you've got spare space then they can be effective in a home or business.

I’m looking at hydrogen, because it’s known tech and I dream of finding a way to use it in a more stable chemical form for storage.

I did the same looking at Hydrogen, and its pretty bleak. Not only is creating hydrogen safely (from electrolysis) difficult, but storage is a nightmare. Any kind of gaseous storage is incredibly difficult because of how small a molecule H2 is, and if you're storage is inside a building that leakage creates explosion risks.

The safest way I saw to store and consume hydrogen is absorbed into a metal hydride. The problem there is that fillers (because of pressure) are expensive $2k for the cheapest one I saw, and you need many metal hydride cylinders to store any appreciable amount of hydrogen. So they end up being large, heavy and bulky or relatively little energy storage.

For home use, a regular lithium battery is so much more efficient and safe.