In any case biodiesel requires large fossil fuel inputs to produce, so it is unlikely to be a long term solution.
You can say the same about solar panels, EV batteries, wind turbines, etc.
Solar panels, EV batteries, wind turbines, etc currently use quite a lot of fossil fuel in their construction. They don't require fossil fuels on an ongoing basis throughout their life. Every litre of biodiesel consumes a lot of fossil fuel in its production. So much that feeding some of the biodiesel back around the production loop, to be used instead of fossil fuels, doesn't currently work out well.
Yes, true. Another difference is that the fossil fuel input to solar panels, batteries and windmill production could be eliminated eventually. Biofuel production in any meaningful quantity on the other hand, requires petrochemical inputs by its very nature.
I'd like to see a source for that bold statement. I really don't see why you would need fossil fuels to create bio-fuels in the future. It simply doesn't make sense. After all fossil fuels are not a component of the end product.
I didn’t say fossil fuels, I said petrochemicals- noy exactly the same. Chemical fertilzers and pesticides are petrochemicals required to produce the needed biomass yield for large quantities of biofuels. Just one example is the use of nat gas in the Haber-Bosch process used to produce nitrogen fertilizer. There are countless examples of pesticides in use that are derived from petrochemicals. And petrochemicals are used in the actual chemical production of the biofuel itself - for example, biodiesel production involves trans-esterification of vegetable oils and fats through the addition of methanol and a catalyst.
You could surely produce some types of biofuels in small amounts without petrochemicals, but never on the scale needed for widespread use.
Solar panels, wind turbines, etc also need energy to be manufactured.
Yes of course they do and I said so above. The difference is that you could produce those with an entirely fossil fuel and petrochemical free process, IF that infrastructure was built. Initially, building that infrastructure would require large fossil fuel inputs, but once built it could in theory be maintained without fossil fuel or petrochemical input. Unfortunately we have not developed that infrastructure and it’s likely too late now. As I’ve said before on this forum, we’ve waited too long and as much as I’d love to see a day when our current standard of high energy living is maintained for the masses with an all electric, fossil fuel free technology, it ain’t gonna happen IMHO.