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My local power utility has ramped up its (thus far) voluntary load shedding campaign this year with rebates for usage reductions during high-demand periods (inc

My local power utility has ramped up its (thus far) voluntary load shedding campaign this year with rebates for usage reductions during high-demand periods (including today!), and is also pushing "smart" thermostats pretty hard, also in exchange for a minor rebate. They're "smart" in that they allow the utility to remotely shut down your AC for a 75% or 50% duty cycle, which you are not allowed to override. Don't count on AC saving all that many lives as the decade wears on.

toomuchtodo 5y ago
Rooftop solar (if you can) is the future. The cost will (must, really) come down, even if we need a "Solar Corps" (volunteers, Habitat for Humanity style) or similar to get generation on the roofs of the disadvantaged. AC load shedding will become untenable in the hottest of places, and the power grid will become taxed from demand faster than infrastructure upgrades can occur.
- cj 5y ago
  Tesla Solar Roof comes to mind. https://www.tesla.com/solarroof https://www.tesla.com/solarroof It’s unfortunately roughly double the cost of a regular roof (and 3x as much if your current roof is already due for replacement).
  - toomuchtodo 5y ago
    In Australia, the cost for rooftop solar is about $1/watt. In the US, we're still higher from soft costs such as permitting, utility review and approval, and similar, putting the cost closer to $2-$3/watt (pre 26% federal tax credit). The NREL recently released an app that automates the permitting process [1], but there are still places to squeeze the fat out to drive the cost down. Tesla's solar tiles are interesting, but cost prohibitive for anyone but the wealthy. [1] https://solarapp.nrel.gov/ https://solarapp.nrel.gov/ (i facilitate, pm, and help with rooftop solar installs as time permits in the US)
  - deleted 5y ago
    [deleted]
- rootusrootus 5y ago
  Rooftop solar is tempting. I'm in the PNW so the economics don't work out favorably (even at $1.5/W installed, which is what I was recently quoted). But there are some non-economic advantages to having solar (as long as you have batteries) so it may still be worthwhile.
  - irrational 5y ago
    I’m in Portland, OR. I’m not sure what you mean by the economics not working out. We got a loan to pay for the solar panels. The loan payment each month is about $35 under our previous monthly electric bill. Any excess electricity our system generates is fed back into the system and we get a credit for it. So far (4 years) it has been enough that even in the cloudiest months we don’t pay anything to PGE above the base charge ($12) to be hooked into the system. Once the loan is paid off (in about 15 years), the panels are guaranteed to still be at 80% efficiency and our electric bill should be minuscule. Either way, the money we are paying is less than what we paid for our electric bill before panels.
    - rootusrootus 5y ago
      The short answer is that I found that roof life expectancy was the real factor in determining whether the system was a good investment. The math is far more favorable if you install a 25 year roof at the same time you install the solar panels (and assuming that you needed to replace the roof anyway, or it was a new install on a freshly built house). Roughly, the math for my situation worked out like this. $20K out of pocket for a 13.5kW system, installed. This should, over a year's time, cover close to 100% of my average consumption. Break-even time was something just over 11 years. Existing roof is 10 years old. Reasonable life expectancy of the roof is 15 more years. Value of panels in 15 years is likely to be dwarfed by uninstall/reinstall costs when roof is replaced, so I call that EOL for the system. The most optimistic scenario I can come up with, assuming PGE raises their rates 2.5% a year, is an ROI of 56K, which works out to about 10% annually. Not bad. But this only happens if nothing breaks, the roof really does last 15 years, the installed cost is only $1.5/W, and I invest $20K out of pocket (i.e. no loans). So the way I see it, this is something to do for the non-economic benefits, e.g. installing battery so it will work when the grid is down.
- Retric 5y ago
  There is quite a bit of room between what most people set their AC, what’s actually uncomfortable, and an even larger gap to what’s unhealthy. That delta is what allows load shedding in a heat wave. They don’t turn off the AC for days it simply goes on a longer cycle so the building might hit say 80f with low humidity. In rich countries like the US throwing money at the problem works, but for the much of the world the extra infrastructure simply isn’t worth the extra comfort.
  - deleted 5y ago
    [deleted]
- mlyle 5y ago
  I'm in California where we have tons of solar generation. For much of the state, solar generation slopes off sharply starting at 4PM and it's still hot. That's when we tend to have the grid emergencies now. Houses with average insulation and pre-heated framing/attics can rise in temperature pretty quickly even if you've aggressively precooled the indoors.
  - toomuchtodo 5y ago
    Does your utility have a battery install incentive (Powerwall, LG Chem, etc) [1]? That’s typically what’s attempting to solve for the evening duck curve ramp in CA [2], enough storage to carry through from sunset to evening demand drop off. [1] https://www.cpuc.ca.gov/industries-and-topics/electrical-energy/demand-side-management/self-generation-incentive-program/participating-in-self-generation-incentive-program-sgip https://www.cpuc.ca.gov/industries-and-topics/electrical-ene... [2] https://www.caiso.com/documents/flexibleresourceshelprenewables_fastfacts.pdf https://www.caiso.com/documents/flexibleresourceshelprenewab...
    - mlyle 5y ago
      Yah, but it's not worth it even with incentive. It's cool for geek factor / having a major UPS and I may go for it for that reason. I think batteries-- distributed or as part of utility-scale deployments-- can help a bit but are not economical enough to use to solve this problem. It's going to take more of everything-- more solar overprovisioning, a lot more wind power, a fair bit of battery, more load shedding and demand pricing, more DC interconnect allowing power to be shipped large distances... and other stuff, like gas-to-power-to-gas and/or more nuclear baseload... to really let us move to an overwhelmingly renewable grid and have stable power. The issue, IMO, is that there's many different timescales/types of shortfall (very cloudy couple weeks in winter with no wind vs. daily duck curve)... and then there's the 1 in 100 and 1 in 1000 events, too (heat wave in summer + overcast rolls in at 2:00PM trapping heat in all night with less insolation and little wind). Chemical storage can't blunt the longer timescale shortfalls much.
Arrath 5y ago
Makes me wonder how hard it would be to either just snip the control circuit from the utility provided thermostat to your AC unit and run your own in its place while retaining the discount, or setup an rPi or such as a MITM and intercept the control commands. Alternatively: just don't overthink things and install a mini-split/window unit/small portable that doesn't get connected to the house thermostat in the first place.
- toomuchtodo 5y ago
  These programs are optional. Google's Nest (among others) integrates with utility signaling to perform this shedding, and it's typically allowable for you to enable cooling and override the load shedding activated during peak demand (in the programs I'm familiar with).
  - Arrath 5y ago
    I get that, I was just pondering the fraudulent possibilities of netting the discount while subverting any control the utility would take over your HVAC equipment.
    - throwanem 5y ago
      You have to have a smart meter to qualify for the program, so it's not like they can't tell if you cheat from consumption data.
  - throwanem 5y ago
    The smart thermostats BGE offers allow only two overrides per day, iirc 30 or 60 min each. Not sure on that part, but the specific period isn't so much at issue as that somebody else has the privilege of deciding when I am allowed not to swelter. (I saw some mention of a "smart switch" also installed under this program, which I assume is there to prevent "overriding" the meter by just yanking it off the wall and shorting the contacts.)
    - toomuchtodo 5y ago
xxpor 5y ago
>they allow the utility to remotely shut down your AC for a 75% or 50% duty cycle, which you are not allowed to override. Switches can be bypassed ;)
- deleted 5y ago
  [deleted]
rdtwo 5y ago
Nobody is going to throttle the ac to your million dollar home unless it’s Cali and even then probably not. Likely will only affect poor people.
- s0rce 5y ago
  I lost power for about 45min last year during one of the highest load days in California. No AC though so it didn't really do much except people went outside and talked about not having power.
- knownjorbist 5y ago
  East coast here, if you elect to participate in the program they can toggle your usage to 75% or 50% with advance notice.
- throwanem 5y ago
  Million-dollar home, that's cute. But that aside, by you I should what? Not give a rat's ass because it doesn't affect me?
  - rdtwo 5y ago
    If you have a west coast home it’s probably worth at least half a mil in any Major metro close to 1 for anything decent sized. People who pay subsidized rates will be throttled but will still be colder than 10 years ago before ac was widely available, they will have to suffer at 80-85f while you crank it down to 68 and pay market rate for the privilege . That’s just how capitalism works and it’s not a bad thing
gizmo686 5y ago
50% duty cycle is more than enough to keep the temperature at a survivable level. If the utilities use the load shedding program to reduce AC usage to the point of killing people, the situation would already be so bad that the alternative load shedding approach of black outs would kill far more people.
- punnerud 5y ago
  It also helps to insulate the house and block the sunlight from the outside of the window. If you only use curtains, all the heat still get inside the house. Norwegian company buildings are not allowed to install AC if you don’t have outside sunscreening. This is to save energy used by AC.

toomuchtodo 5y ago

Rooftop solar (if you can) is the future. The cost will (must, really) come down, even if we need a "Solar Corps" (volunteers, Habitat for Humanity style) or similar to get generation on the roofs of the disadvantaged. AC load shedding will become untenable in the hottest of places, and the power grid will become taxed from demand faster than infrastructure upgrades can occur.

cj 5y ago
Tesla Solar Roof comes to mind. https://www.tesla.com/solarroof https://www.tesla.com/solarroof It’s unfortunately roughly double the cost of a regular roof (and 3x as much if your current roof is already due for replacement).
- toomuchtodo 5y ago
  In Australia, the cost for rooftop solar is about $1/watt. In the US, we're still higher from soft costs such as permitting, utility review and approval, and similar, putting the cost closer to $2-$3/watt (pre 26% federal tax credit). The NREL recently released an app that automates the permitting process [1], but there are still places to squeeze the fat out to drive the cost down. Tesla's solar tiles are interesting, but cost prohibitive for anyone but the wealthy. [1] https://solarapp.nrel.gov/ https://solarapp.nrel.gov/ (i facilitate, pm, and help with rooftop solar installs as time permits in the US)
- deleted 5y ago
  [deleted]
rootusrootus 5y ago
Rooftop solar is tempting. I'm in the PNW so the economics don't work out favorably (even at $1.5/W installed, which is what I was recently quoted). But there are some non-economic advantages to having solar (as long as you have batteries) so it may still be worthwhile.
- irrational 5y ago
  I’m in Portland, OR. I’m not sure what you mean by the economics not working out. We got a loan to pay for the solar panels. The loan payment each month is about $35 under our previous monthly electric bill. Any excess electricity our system generates is fed back into the system and we get a credit for it. So far (4 years) it has been enough that even in the cloudiest months we don’t pay anything to PGE above the base charge ($12) to be hooked into the system. Once the loan is paid off (in about 15 years), the panels are guaranteed to still be at 80% efficiency and our electric bill should be minuscule. Either way, the money we are paying is less than what we paid for our electric bill before panels.
  - rootusrootus 5y ago
    The short answer is that I found that roof life expectancy was the real factor in determining whether the system was a good investment. The math is far more favorable if you install a 25 year roof at the same time you install the solar panels (and assuming that you needed to replace the roof anyway, or it was a new install on a freshly built house). Roughly, the math for my situation worked out like this. $20K out of pocket for a 13.5kW system, installed. This should, over a year's time, cover close to 100% of my average consumption. Break-even time was something just over 11 years. Existing roof is 10 years old. Reasonable life expectancy of the roof is 15 more years. Value of panels in 15 years is likely to be dwarfed by uninstall/reinstall costs when roof is replaced, so I call that EOL for the system. The most optimistic scenario I can come up with, assuming PGE raises their rates 2.5% a year, is an ROI of 56K, which works out to about 10% annually. Not bad. But this only happens if nothing breaks, the roof really does last 15 years, the installed cost is only $1.5/W, and I invest $20K out of pocket (i.e. no loans). So the way I see it, this is something to do for the non-economic benefits, e.g. installing battery so it will work when the grid is down.
Retric 5y ago
There is quite a bit of room between what most people set their AC, what’s actually uncomfortable, and an even larger gap to what’s unhealthy. That delta is what allows load shedding in a heat wave. They don’t turn off the AC for days it simply goes on a longer cycle so the building might hit say 80f with low humidity. In rich countries like the US throwing money at the problem works, but for the much of the world the extra infrastructure simply isn’t worth the extra comfort.
- deleted 5y ago
  [deleted]
mlyle 5y ago
I'm in California where we have tons of solar generation. For much of the state, solar generation slopes off sharply starting at 4PM and it's still hot. That's when we tend to have the grid emergencies now. Houses with average insulation and pre-heated framing/attics can rise in temperature pretty quickly even if you've aggressively precooled the indoors.
- toomuchtodo 5y ago
  Does your utility have a battery install incentive (Powerwall, LG Chem, etc) [1]? That’s typically what’s attempting to solve for the evening duck curve ramp in CA [2], enough storage to carry through from sunset to evening demand drop off. [1] https://www.cpuc.ca.gov/industries-and-topics/electrical-energy/demand-side-management/self-generation-incentive-program/participating-in-self-generation-incentive-program-sgip https://www.cpuc.ca.gov/industries-and-topics/electrical-ene... [2] https://www.caiso.com/documents/flexibleresourceshelprenewables_fastfacts.pdf https://www.caiso.com/documents/flexibleresourceshelprenewab...
  - mlyle 5y ago
    Yah, but it's not worth it even with incentive. It's cool for geek factor / having a major UPS and I may go for it for that reason. I think batteries-- distributed or as part of utility-scale deployments-- can help a bit but are not economical enough to use to solve this problem. It's going to take more of everything-- more solar overprovisioning, a lot more wind power, a fair bit of battery, more load shedding and demand pricing, more DC interconnect allowing power to be shipped large distances... and other stuff, like gas-to-power-to-gas and/or more nuclear baseload... to really let us move to an overwhelmingly renewable grid and have stable power. The issue, IMO, is that there's many different timescales/types of shortfall (very cloudy couple weeks in winter with no wind vs. daily duck curve)... and then there's the 1 in 100 and 1 in 1000 events, too (heat wave in summer + overcast rolls in at 2:00PM trapping heat in all night with less insolation and little wind). Chemical storage can't blunt the longer timescale shortfalls much.

Arrath 5y ago

Makes me wonder how hard it would be to either just snip the control circuit from the utility provided thermostat to your AC unit and run your own in its place while retaining the discount, or setup an rPi or such as a MITM and intercept the control commands. Alternatively: just don't overthink things and install a mini-split/window unit/small portable that doesn't get connected to the house thermostat in the first place.

toomuchtodo 5y ago
These programs are optional. Google's Nest (among others) integrates with utility signaling to perform this shedding, and it's typically allowable for you to enable cooling and override the load shedding activated during peak demand (in the programs I'm familiar with).
- Arrath 5y ago
  I get that, I was just pondering the fraudulent possibilities of netting the discount while subverting any control the utility would take over your HVAC equipment.
  - throwanem 5y ago
    You have to have a smart meter to qualify for the program, so it's not like they can't tell if you cheat from consumption data.
- throwanem 5y ago
  The smart thermostats BGE offers allow only two overrides per day, iirc 30 or 60 min each. Not sure on that part, but the specific period isn't so much at issue as that somebody else has the privilege of deciding when I am allowed not to swelter. (I saw some mention of a "smart switch" also installed under this program, which I assume is there to prevent "overriding" the meter by just yanking it off the wall and shorting the contacts.)
  - toomuchtodo 5y ago

xxpor 5y ago

>they allow the utility to remotely shut down your AC for a 75% or 50% duty cycle, which you are not allowed to override. Switches can be bypassed ;)

deleted 5y ago
[deleted]

rdtwo 5y ago

Nobody is going to throttle the ac to your million dollar home unless it’s Cali and even then probably not. Likely will only affect poor people.

s0rce 5y ago
I lost power for about 45min last year during one of the highest load days in California. No AC though so it didn't really do much except people went outside and talked about not having power.
knownjorbist 5y ago
East coast here, if you elect to participate in the program they can toggle your usage to 75% or 50% with advance notice.
throwanem 5y ago
Million-dollar home, that's cute. But that aside, by you I should what? Not give a rat's ass because it doesn't affect me?
- rdtwo 5y ago
  If you have a west coast home it’s probably worth at least half a mil in any Major metro close to 1 for anything decent sized. People who pay subsidized rates will be throttled but will still be colder than 10 years ago before ac was widely available, they will have to suffer at 80-85f while you crank it down to 68 and pay market rate for the privilege . That’s just how capitalism works and it’s not a bad thing

gizmo686 5y ago

50% duty cycle is more than enough to keep the temperature at a survivable level. If the utilities use the load shedding program to reduce AC usage to the point of killing people, the situation would already be so bad that the alternative load shedding approach of black outs would kill far more people.

punnerud 5y ago
It also helps to insulate the house and block the sunlight from the outside of the window. If you only use curtains, all the heat still get inside the house. Norwegian company buildings are not allowed to install AC if you don’t have outside sunscreening. This is to save energy used by AC.