• humanspiral@lemmy.ca
    link
    fedilink
    English
    arrow-up
    1
    ·
    3 hours ago

    The economics of batteries are that they must be fully charged and discharged daily to pay off. A 2 day average cycle is double the cost of energy in using them.

    In spring and fall we get positive happy headlines that “all electricity was provided by solar/renewables” during 1 hour or so during a day, or that electricity prices went negative. These seasons are low demand with good enough sun. Batteries get let those days/seasons get to 24 hour power from renewables, but then summer heatwaves won’t fill demand even with more sun, winter will not charge up the batteries enough. H2 electrolysis is needed to have enough solar and batteries to cover all those needs, and then use H2 to cover winter supplemental needs. H2 supports not just more solar, but also more batteries. Makes sure batteries can always discharge before the sun comes up.

    imagine refueling times is not necessarily going to be critical for all types of commercial use-cases.

    Commercial vehicles, need to pay operators for downtime, and downtime is time not earning revenue. it is a bid deal to them.

    Aviation struggles with the relatively low energy density in H2.

    At $4/gallon diesel/kerosene, a plane will cost 100x in fuel as its purchase costs. We can already produce green H2 at $2/kg compressed. Which is equivalent to $1/gallon gasoline fuel when used in a FC. Redesigning planes, and delta wing for long range specifically, for H2 is worth liquifying the H2 for the weight savings and range over compressed. It’s also that price that can compete well with commercial EV charging.