Hacker News new | ask | show | jobs
by jakewins 80 days ago
Respectfully, 30kWh is not much in this context. In 10 years every modern 2-car home will have 200kWh on the driveway just from the EVs; add a 100kWh whole home battery at a price point close to a 10kWh battery today and the calculus changes in most of the world.

The cost of materials going into modern batteries easily leaves room for another 10x reduction in price, IMO where this all is heading is obvious. Zero marginal cost will win every day of the week.

FWIW we run our cabin on 15kWh battery today year around, though we do run a small wood stove to supplant the heat pump on cold winter days.

2 comments

40 kWH of storage and 9 kW of solar panels is all I need personally to live a 1st world lifestyle in the bay area mostly off-grid except for water and internet.
Bay Area is ideal climate to accomplish this.
PNW is fraught, amazing during the Summer, but underpowered in Winter. The best solution is overprovisioning panels by a factor of 4 or so if the room is available. Did a place up there and it's hugely overproductive half the year, and just under break even in the dead of Winter.

From the Bay area or so and down across the country is ideal for solar, passing through a lot of red states that ought to know better. Fun fact though: Texas has the most windmills of any state by a huge margin.

I bet you didn't even see the tragic farce when writing your solution. Land development requiring ”2-car homes" is the driver of the problem! An apartment only has to heat one or two walls facing the outside instead of 4. That's 50-75% right off the top of your energy usage, with the mean closer to 75%.
There's nothing farcical about wanting one's own space where there's space to have one's own space. I'm grateful to no longer be sharing walls with a domestic abuse couple on one side and a midnight banshee on the other wall when she got busy. Energy is cheap, people are exhausting.
And that gets into another coordination problem we're unable to solve. It's a solved problem to build apartments where you can't hear your neighbors, but the builders don't have incentive to spend the money upfront to do so and we add regulations to make it more expensive for them to do so. So people go on thinking "apartments suck" and not the correct "we shouldn't let people build apartments which suck".

Also, living in SFH isn't avoiding all problems. I'd rather live in a properly-built apartment than my old house when my neighbor left her dogs outside to bark for the entire work day, every single day, and all the city would do is fine her a hundred bucks every few months. (or if you want to say "rural", that's 1 a small fraction of the population and 2 I like hospitals).

And the usual engineer mindset to consider the options to be 1 or 0, no?

I just live far enough from the center of it all that I have a vacant quarter acre and thicker windows that happened when the last owner's mistakes caught up with me the current owner. For medical, I have UCSF, and for major medical, I have medical tourism, something I fully endorse from experience. And yes, not everyone can do that. And well, I can't touch my toes and they probably can. Life's funny that way.

No reason to be rude or hyperbolic - I agree with you that cars destroy communities and we should strive to reduce the need for cars and parking.

For solar powered homes specifically though, multi-story buildings are much harder to run solar powered from the simple ratios - even if you reduce energy use 75%, at 4 stories you are break-even in roof-ratio-to-energy-need. I’ve worked in this space a while, and it’s now pretty straight forward to run single-family homes 24/7/367 on solar in most of the world, but multi story buildings are much harder.

Nothing is ever simple or one-dimensional :)

I mostly agree with you, however...

You don't need to colocate solar at the point it's used. Utility solar is cheaper than rooftop, by multiple.

The last part isn't true. There's no way you're running a home, including heat, entirely of solar in the winter in the Upper Peninsula of Michigan.

Utility solar is cheaper in studies that do not factor in the cost of distribution, but the picture is much less clear when total system cost is considered - not having to pay for expanded distribution grids or new interconnects is a major benefit of residential production.

As for the last part not being true, can you clarify? The majority of the earths population lives between the 20th and 40th latitude, the band around the earth approximately between Madrid and the Sahara desert. Sure you can’t run a poorly insulated home in northern Michigan on solar year around without considerable expense, but that’s nowhere near where the majority of humanity lives.

I misread you as saying all homes. You're right that anywhere that's sunny year round, a SFH can be self-sufficient for electricity with photovoltaic and batteries.