fixed, thanks

Almost all innovation is stupid until it works

I know that's a common saying, but I don't think I agree. Were smaller transistors a stupid idea until they worked? And then, there are some "good ideas" that were in a sense still "stupid" for a while after they started working, like some impractical early rocket weapons.

I honestly don't know which direction this should move your opinion of Hyundai's research agenda.

I don't think it should affect your opinion of "Hyundai's research agenda" much at all. This is just normal.

For starters, see this and this. To summarize:

• They're using D-He3 fusion to make less neutrons, because they want to capture electricity directly from the plasma, but that's harder than D-T fusion.
• Plasma has MHD instabilities, which are also why solar flares happen. These are worse at higher power levels. Devices of the type Helion uses have been unable to manage conditions that produce much fusion, even D-T fusion, without instabilities getting bad.
• Helion has said they rely on particle gyroradius in magnetic fields being comparable to plasma size for stability. But fusion requires many collisions, inevitably, so most particles would then escape before fusing.

There is no solution for their approach.

Those projected numbers seem to just be made up, extrapolated from graphs and hopes by consultants rather than based on proper techno-economic analysis.

I don't expect Na-ion to be cheaper than Li-ion. The disadvantages seem to outweigh lower material costs.

They're very different, and there are many possible types of both. To guess at what you want to know:

• I don't expect Na-ion batteries to replace Li-ion.
• Flow batteries have separate costs for power and capacity, while those are linked in Li-ion and Na-ion. Flow batteries only make sense when charging and discharging over at least a few hours.

Thanks.

charging time of 10% of usage time is relatively normal

Charge time partly depends on power available, but is typically set to 1 hour to reduce battery degradation. Discharge time depends on battery size relative to power usage. They're not directly related.

have stated that they believe cost per kWh can come down to $40/kWh

I understand battery chemistry fairly well, and my view is, they're lying for strategic reasons.

commonly expected/roadmapped to be ~$1.5/kg H2

see this post for my comments

Any time overhead electrical lines for mining trucks would be worthwhile, overland conveyors are usually better.

At a ROI of 19% you get economic payback in 5.3 years. The benefits are more weighted towards fossil fuel use than the costs so CO2 neutrality would be sooner than that, but then you start getting into issues like how you account for energy usage of workers whose labor is being used when you substitute labor for energy use.

No. Trains that can do that are called electro-diesel locomotives. Not diesel-electric.

For the most part, these locomotives are built to serve regional, niche markets with a very specific purpose.

You're using Grainger list prices? Seriously? If you actually dealt with buying stuff for industry, you'd know that their prices are much lower when you have a big account with them, and that there are cheaper options.