Keep hammering the point that they are cheaper. If they are open to more advanced discussion point to the amazing structural changes that batteries are only starting to bring. Tell them something that sounds mildly like science fiction but is in fact happening already and will be HUGE. E.g. the battery you’ll have in your AC/stove/car will save you money or even make you money when part of a smart mesh of DERs.

Maybe I’m too optimistic :)

It's a challenge, but remember that there is a lot of money in trying to convince people about the status quo. I'd keep in mind the kind of tactics that fossil fuel companies will be using to convince people otherwise:

- Using old data - the price of renewables and storage technology have fallen through the floor but bad actors are quite happy to use outdated numbers to convince you that they're not cheap

- Ignoring existing downsides - renewables have issues and we shouldn't forget that, but it's easy to forget what we're replacing. e.g. Lithium mines are environmentally unfriendly, but you dig it out of the ground and turn it into a battery once (and bonus - it's recyclable). Oil and gas must be continually dug out of the ground and burned

- But China... - I don't think most people realise quite how quickly the rest of the world is pushing on with renewables

In fact, it's very easy to reason them to change their minds:

1. Take statistics from any of these excellent solar power plants for, say, five years time span

2. Find the worst week in terms of energy production in these statistics

3. Explain to the renewable energy skeptic how this 20+ times drop in productivity will be compensated for users

4. The skeptic is successfully convinced and becomes a renewable energy proponent