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What prevents cheap home lithium power? It seems easier for powerwall derivitives to become cheaper than solar because the % total cost of ownership not attrib

What prevents cheap home lithium power? It seems easier for powerwall derivitives to become cheaper than solar because the % total cost of ownership not attributable to batteries is less. For example, it may not require a bunch of people on your roof, maybe less permit or zoning related costs, maybe less electrician labor, etc. Why couldn't a startup with a couple of EE's design something comparable or maybe even something with ease of installation innovations using commodity battery cells? Couldn't they buy cells in small batches online at first, paying notch or two higher than wholesale until they ramp up sales? Not sure how it couldn't start as a garage business for a clever engineer undergraduate and a clever sales/marketing/distribution person. I mean, people are already rolling their own as side projects right (without going into the practicality or safety of that, just in reference to the barriers to entry)?

slfnflctd 8y ago
This would be really nice to see. I started looking into emerging battery tech eight or ten years ago, and was really excited-- between approaches using compressed air storage (ha), liquid metal, saltwater, molten salt and new ways of using cobalt, I was convinced consumer price per kWh was about to be slashed in half by someone, somewhere, at least for stationary battery arrays. Since then, most of my enthusiasm about potential new products, bundles and kits that could be driven by this has steadily evaporated as consumer price per kWh for actual, usable power storage has more or less held steady. At this point I'm just as curious what's keeping it stuck there as I am about what we could do if it wasn't.
zackmorris 8y ago
Part of the problem is grid tie inverters. 1 kW used to cost about 10 times more than the equivalent 1 kW computer power supply, but prices have finally dropped to the point where they are comparable (roughly $100/kW): https://www.ebay.com/sch/i.html?_nkw=grid+tie+inverter https://www.ebay.com/sch/i.html?_nkw=grid+tie+inverter https://www.amazon.com/s?k=grid+tie+inverter https://www.amazon.com/s?k=grid+tie+inverter IMHO power converters like these are the future, because eventually we'll plug in all noisy sources of power from wind/solar/thermal into an inverter that accepts any voltage and plugs into the wall to provide 110 V AC. So roughly 12 of these (for a typical 100 amp system) would power the average home, meaning the inverter portion of a Powerwall should cost no more than $1200.
pjc50 8y ago
The cells themselves are the expensive bit. There have been one or two people doing it as recreational projects but obviously Tesla's vertical integration and large production run will win over the garage tinkerer. Not to mention that selling an unsafe product is a non starter. No, the interesting thing to me is why everyone forgot about the other chemistries like NiFe, which are cheaper but heavier - matters less for a fixed installation. Also I feel that proper net metering should be better than domestic batteries for the normal case. The only reason it isn't is regulatory spinelessness.
- Tuna-Fish 8y ago
  > The only reason it isn't is regulatory spinelessness. The reason it isn't widely used is because it is an absolutely terrible idea. The value of home solar fed to the grid is almost everywhere negative to the utility. (They need to maintain fixed capacity to meet worst case demand, constant power sources are cheaper than adjustable ones, and it costs money to bleed off excess power when there is not enough demand for it.) If you force them to pay you for your useless solar excess, they just have to raise the prices on everyone. This makes home solar more attractive, resulting in even larger useless peak production, and higher electricity prices. It gets even worse if the power transmission isn't decoupled from production. A form that would make sense is instead to allow customers to sell electricity back to the utility at the current short term spot price. As excess production would drive that price to be negative, it would limit installation to the level that is healthy to the grid.
  - pjc50 8y ago
    > The value of home solar fed to the grid is almost everywhere negative to the utility [citation needed] Also, being of negative value to the utility is not the same as negative value to society! Is it displacing carbon-based generation? Is it reducing the need to buildout power lines? > costs money to bleed off excess power when there is not enough demand for it This doesn't happen during the day. Very occasionally some wind farms get curtailment payments at 3am or similar. There are no giant resistor banks to dump energy. > force them to pay you for your useless solar excess, they just have to raise the prices on everyone Economics 101: producing more of a product makes it more expensive! No, wait, the other thing. > constant power sources are cheaper than adjustable ones Be specific: nuclear (no longer really being built, surprisingly expensive) or coal (phasing out)? In the UK it mostly displaces dispatchable CCGT: https://www.gridwatch.templar.co.uk/ https://www.gridwatch.templar.co.uk/ (Some of these problems might appear at 10x the current solar market penetration, but most of them are just anticompetitive complaints by utilities because solar shows up as negative demand)

slfnflctd 8y ago

This would be really nice to see. I started looking into emerging battery tech eight or ten years ago, and was really excited-- between approaches using compressed air storage (ha), liquid metal, saltwater, molten salt and new ways of using cobalt, I was convinced consumer price per kWh was about to be slashed in half by someone, somewhere, at least for stationary battery arrays. Since then, most of my enthusiasm about potential new products, bundles and kits that could be driven by this has steadily evaporated as consumer price per kWh for actual, usable power storage has more or less held steady. At this point I'm just as curious what's keeping it stuck there as I am about what we could do if it wasn't.

zackmorris 8y ago

Part of the problem is grid tie inverters. 1 kW used to cost about 10 times more than the equivalent 1 kW computer power supply, but prices have finally dropped to the point where they are comparable (roughly $100/kW): https://www.ebay.com/sch/i.html?_nkw=grid+tie+inverter https://www.ebay.com/sch/i.html?_nkw=grid+tie+inverter https://www.amazon.com/s?k=grid+tie+inverter https://www.amazon.com/s?k=grid+tie+inverter IMHO power converters like these are the future, because eventually we'll plug in all noisy sources of power from wind/solar/thermal into an inverter that accepts any voltage and plugs into the wall to provide 110 V AC. So roughly 12 of these (for a typical 100 amp system) would power the average home, meaning the inverter portion of a Powerwall should cost no more than $1200.

pjc50 8y ago

The cells themselves are the expensive bit. There have been one or two people doing it as recreational projects but obviously Tesla's vertical integration and large production run will win over the garage tinkerer. Not to mention that selling an unsafe product is a non starter. No, the interesting thing to me is why everyone forgot about the other chemistries like NiFe, which are cheaper but heavier - matters less for a fixed installation. Also I feel that proper net metering should be better than domestic batteries for the normal case. The only reason it isn't is regulatory spinelessness.

Tuna-Fish 8y ago
> The only reason it isn't is regulatory spinelessness. The reason it isn't widely used is because it is an absolutely terrible idea. The value of home solar fed to the grid is almost everywhere negative to the utility. (They need to maintain fixed capacity to meet worst case demand, constant power sources are cheaper than adjustable ones, and it costs money to bleed off excess power when there is not enough demand for it.) If you force them to pay you for your useless solar excess, they just have to raise the prices on everyone. This makes home solar more attractive, resulting in even larger useless peak production, and higher electricity prices. It gets even worse if the power transmission isn't decoupled from production. A form that would make sense is instead to allow customers to sell electricity back to the utility at the current short term spot price. As excess production would drive that price to be negative, it would limit installation to the level that is healthy to the grid.
- pjc50 8y ago
  > The value of home solar fed to the grid is almost everywhere negative to the utility [citation needed] Also, being of negative value to the utility is not the same as negative value to society! Is it displacing carbon-based generation? Is it reducing the need to buildout power lines? > costs money to bleed off excess power when there is not enough demand for it This doesn't happen during the day. Very occasionally some wind farms get curtailment payments at 3am or similar. There are no giant resistor banks to dump energy. > force them to pay you for your useless solar excess, they just have to raise the prices on everyone Economics 101: producing more of a product makes it more expensive! No, wait, the other thing. > constant power sources are cheaper than adjustable ones Be specific: nuclear (no longer really being built, surprisingly expensive) or coal (phasing out)? In the UK it mostly displaces dispatchable CCGT: https://www.gridwatch.templar.co.uk/ https://www.gridwatch.templar.co.uk/ (Some of these problems might appear at 10x the current solar market penetration, but most of them are just anticompetitive complaints by utilities because solar shows up as negative demand)