Give us more affordable and higher capacity batteries and hydrogen energy storage for vehicles make no sense.

I’ve got far more solar panels than I need for sunny days like today.  My batteries were full before 10am.  That means hours of wasted energy that could be flowing somewhere else and reducing fossil fuel useage.

I’ve got far too few solar panels than I need for cloudy days.  I can’t get close to producing all my electricity needs during a string of overcast days.  I have to crank up the generator and burn fossil fuel. I wish I could grab some of the excess wind or hydro that my neighbors are producing.

—

Seasonal storage using hydrogen. We don’t have numbers to let us start understanding the cost of our options.  One thing about hydrogen, we could build up the supply over time, meaning that we could build less generation.  

But we’d have to be able to turn that hydrogen into electricity in large volumes which would mean a lot of fuel cells/whatever.  A big investment.

If we just over-sized all the distributed battery installations that we’re likely to end up with we would only have to add extra batteries.  We could charge them with the same AC -> DC equipment we would use for grid smoothing and short term storage.  Then we could use the same inverters we use for short term storage, just run them all at full output, all at the same time.

Many remote vacation houses or boats have an off-grid installation with batteries. But it is very expensive and can not guarantee 100% availability. On a specific site, the sun can hide behind the clouds for many days or even weeks. The batteries would be way more expensive than the monthly fee for a grid connection.

It is not efficient to turn each house into an energy island. Eliminating over/underproduction on site will require vast amounts of storage, much larger than when you first combine all generators (different technologies) over a large area and then deal with the remaining variability.

Also, many houses (eg apartments)  do not have enough roof available to generate all their energy on site and go off-grid.

To flatten the day/night curve, batteries are much cheaper than hydrogen
and will be for the forseeable future. Seasonal storage is another
question, there might be a role for hydrogen there.

You’d have to purchase a ‘water cracker’. 

You’d have to purchase hydrogen storage including equipment to pressurize the hydrogen (or get a really big tank).

And you’d have to purchase equipment to convert hydrogen back into electricity.

Along with that you’d lose a lot of the energy you put in the front end.

My money is on batteries.

—

And, no, I don’t see the end of power/utility companies.  A lessor role, yes, but many people are not either able or willing to set up their own power companies.  

And stand-alone systems are very much less efficient than large grid systems that can bring power from a variety of sources and locations.

I don’t see hydrogen powered vehicles as likely.  If EV batteries increase about 50% in capacity and fall to an affordable price point then EVs will likely lock in the market.

For hydrogen FECVs to take the market away from EVs they would have to be significantly cheaper to own and operate.  You’d have to get fuel cells well below the price of batteries and distribute hydrogen for well under “$1/gallon”.

Unless there is a major economic advantage for hydrogen fueled driving it would make no sense to invest the many billions of dollars to install a hydrogen generation/distribution system.

Producing hydrogen from methane doesn’t solve the problem of CO2 emission, or could even worsen climate change, depending on how much of the methane leaks during the extraction of natural gas.

So, the other route is producing hydrogen by electrolysis with renewable electricity. This is less than 50% efficient. We can not afford to waste that much energy.

For example. The Honda FCX Clarity can run 60 miles per kg of hydrogen. Producing 1 kg of compressed hydrogen by electrolysis costs ~60 kWh/kg. So the wind-to-wheel efficiency of the Clarity is 1 mile per kWh. The Nissan LEAF travels 3 miles per kWh by using the electricity directly. Some good progress is needed in this area before the hydrogen car becomes an attractive option.