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The book The Grid by Gretchen Bakke is a great primer on why this is such an important problem. Energy is strange, in the sense that everything produced needs t

The book The Grid by Gretchen Bakke is a great primer on why this is such an important problem. Energy is strange, in the sense that everything produced needs to be consumed more or less immediately — it's not like other resources that can be easily stockpiled (even with batteries). Our infrastructure, at least the antiquated American power grid infrastructure, is built with the assumption that production and consumption is balanced. Maintaining the energy grid is a careful balancing act between preventing surges and blackouts. There are a lot of grid-related engineering problems that come from increasing decentralization (e.g. wind, solar, hydro) because, as you mentioned, it increases unpredictability in supply.

dmix 6y ago
Did the book explore every home getting a vanadium redox or lithium battery? It seems like something that will be needed in the future (further adding to the decentralization). This of course will be expensive and I'm not sure how well tall condo buildings will handle the costs. It could potentially increase the cost of buying a home in the future. Or significant investment from the government so we don't regress our back to having blackouts (especially when it puts even more pressure on the poor in the name of the environment)... either to homes or some centralized system.
- Gibbon1 6y ago
  Interesting rabbit hole. I bought an Engel dual 120V/12V powered fridge. Runs off 120VAC and 12-24VDC. You can plug it into both and it switches automatically to 12VDC if the 120VAC drops out. Things I've noticed. Even high efficiency residential fridges aren't that efficient. Some off grid ones use three times less power. And lot of the modern fridges have inverters to drive the compressor. Which means would not that big a stretch to add a 12/24V input like my portable fridge. I mention this because not all household loads are the same. You really don't want your fridge to stop working. You probably can manage if you can't run you whole house air conditioner full tilt. Having appliances that can run off back up and ones that can adjust their load probably would help. Another random opinion is a lot of house wiring could be replaced with Power of Ethernet. There is a new automotive standard that provides up to 100W. A house where lights and light loads were run off POE could be trivially backed up by a battery.
  - sandworm101 6y ago
    POE is limited to 30w. That is enough for a few LED bulbs, and by few I mean like two or three.
    - Gibbon1 6y ago
      You are wrong, IEEE 802.3bt type 4 is good for 100W.
      - sandworm101 6y ago
        Ok, old POE standard in my head, but 100W is still only a handful of fixtures on a circuit.
        FooHentai 6y ago
        Not an issue with PoE since you're running a cable out to each device rather than linking them in a loop/circuit. But then that highlights the problem with trying to PoE and entire house - You have to run a line out from a PoE source to each item you want to deliver power to, and provide a port for each which comes at some cost. I guess you could try and run some kind of PoE passthrough circuit arrangement like you see with some office voip phones... Complicated.
        core-questions 6y ago
        That's ten 10W LEDs which is enough for most moderately sized rooms, and you can just run another cable if need be. I gotta imagine 100W PoE requires some bigger cables than plain-jane Cat5E or even Cat6, though...?
        Dylan16807 6y ago
        The main design goal is to use normal cables. It's half an amp per wire max, which works out fine. The higher power levels require that you take into account how each cable is going to safely dissipate a couple watts, which is easy if you're not running big bundles.
gwright 6y ago
> Our infrastructure, at least the antiquated American power grid infrastructure, is built with the assumption that production and consumption is balanced. All power grids require that balancing. Old, new, American, non-American ...
WalterBright 6y ago
> it's not like other resources that can be easily stockpiled (even with batteries) HVAC usage can be stockpiled in the thermal mass of the house. The same with the electric water heater - the thermal mass of the water in the tank. This is where variable electric rates come in, and smart HVAC/heater systems that run mostly when electricity is cheap.

dmix 6y ago

Did the book explore every home getting a vanadium redox or lithium battery? It seems like something that will be needed in the future (further adding to the decentralization). This of course will be expensive and I'm not sure how well tall condo buildings will handle the costs. It could potentially increase the cost of buying a home in the future. Or significant investment from the government so we don't regress our back to having blackouts (especially when it puts even more pressure on the poor in the name of the environment)... either to homes or some centralized system.

Gibbon1 6y ago
Interesting rabbit hole. I bought an Engel dual 120V/12V powered fridge. Runs off 120VAC and 12-24VDC. You can plug it into both and it switches automatically to 12VDC if the 120VAC drops out. Things I've noticed. Even high efficiency residential fridges aren't that efficient. Some off grid ones use three times less power. And lot of the modern fridges have inverters to drive the compressor. Which means would not that big a stretch to add a 12/24V input like my portable fridge. I mention this because not all household loads are the same. You really don't want your fridge to stop working. You probably can manage if you can't run you whole house air conditioner full tilt. Having appliances that can run off back up and ones that can adjust their load probably would help. Another random opinion is a lot of house wiring could be replaced with Power of Ethernet. There is a new automotive standard that provides up to 100W. A house where lights and light loads were run off POE could be trivially backed up by a battery.
- sandworm101 6y ago
  POE is limited to 30w. That is enough for a few LED bulbs, and by few I mean like two or three.
  - Gibbon1 6y ago
    You are wrong, IEEE 802.3bt type 4 is good for 100W.
    - sandworm101 6y ago
      Ok, old POE standard in my head, but 100W is still only a handful of fixtures on a circuit.
      - FooHentai 6y ago
        Not an issue with PoE since you're running a cable out to each device rather than linking them in a loop/circuit. But then that highlights the problem with trying to PoE and entire house - You have to run a line out from a PoE source to each item you want to deliver power to, and provide a port for each which comes at some cost. I guess you could try and run some kind of PoE passthrough circuit arrangement like you see with some office voip phones... Complicated.
      - core-questions 6y ago
        That's ten 10W LEDs which is enough for most moderately sized rooms, and you can just run another cable if need be. I gotta imagine 100W PoE requires some bigger cables than plain-jane Cat5E or even Cat6, though...?
        Dylan16807 6y ago
        The main design goal is to use normal cables. It's half an amp per wire max, which works out fine. The higher power levels require that you take into account how each cable is going to safely dissipate a couple watts, which is easy if you're not running big bundles.

gwright 6y ago

> Our infrastructure, at least the antiquated American power grid infrastructure, is built with the assumption that production and consumption is balanced. All power grids require that balancing. Old, new, American, non-American ...

WalterBright 6y ago

> it's not like other resources that can be easily stockpiled (even with batteries) HVAC usage can be stockpiled in the thermal mass of the house. The same with the electric water heater - the thermal mass of the water in the tank. This is where variable electric rates come in, and smart HVAC/heater systems that run mostly when electricity is cheap.