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There is an interesting part about solar generating electricity when its sunny - it will help population move to warmer climes. If you live in Ohio heating in w

by rb808 8y ago

There is an interesting part about solar generating electricity when its sunny - it will help population move to warmer climes. If you live in Ohio heating in winter is a problem, solar isn't going to keep you warm on a cold night (ok batteries can help but they're expensive). If you live in the South West though its perfect as Winter nights dont require much heat and the biggest loads are AC at the times when there is lots of sun. Perhaps this will mean living in Southern California, Arizona etc will be increasingly popular as energy costs will be much more affordable. Of course water is the next problem, but cheap electricity can help that too.

stcredzero 8y ago
If you live in Ohio that is a problem, solar isn't going to keep you warm on a cold night Houses built to the German Passivhaus standard would do just fine in Ohio. I used to live in Ohio and Western Pennsylvania, so I should know. There was one Minnesota church built with polystyrene panels that had to start running air conditioning in the middle of winter, the insulation was so good. If you live in the South West though its perfect as Winter nights dont require much heat and the biggest loads are AC at the times when there is lots of sun. It can get pretty darn cold at night in the desert southwest. Again, insulation is the key. Of course water is the next problem, but cheap electricity can help that too. It's 10X as expensive to use techniques like desalinization. It's so much more expensive, that lots of desal plants get built, then get mothballed because it's that much cheaper to get water by other means.
- sharkmerry 8y ago
  is the expense of desalinization the electricity? Which would go down with adoption of solar?
  - stcredzero 8y ago
    You also have to maintain equipment, but I think the electricity is the major thing.
  - jerf 8y ago
    I imagine the idea is something more like one way to dump excessive solar capacity would be to desalinate water during the times of maximum power generation. Or perhaps I just steelmanned the argument.
  - philipkglass 8y ago
    This is a decade old, but I think that the proportions are still about right: https://desline.com/Geneva/Banat.pdf https://desline.com/Geneva/Banat.pdf See the slide "Cost composition for a typical seawater RO (reverse osmosis) plant" Fixed charges (primarily capital cost): 31% Energy: 26% Maintenance and parts: 14% Membrane replacement: 13% Supervision and labor: 9% Chemicals: 7% Really cheap solar electricity could reduce the second largest expense (energy costs), but right now that's just an improvement for daylight hours. Battery-stored solar electricity is getting cheaper but it's not cheap enough to actually reduce nighttime desalination costs yet. And if you run the plant only during the day, you get less value out of the very largest expense (capital cost).
    - rsynnott 8y ago
      That's reverse osmosis. In a scenario where energy is very cheap (even if only for part of the day) there are other processes which require less maintenance, but more energy.
      - philipkglass 8y ago
        The previous slide in that presentation also shows a cost breakdown for a thermal process, multi-stage flash desalination. Fixed charges (primarily capital cost) 42% Energy 41% Maintenance and parts 8% Supervision and labor 7% Chemicals 2% Energy is nearly even with fixed costs for MSF, but fixed costs are even larger here. Leaving this type of plant idle between dusk and dawn would again raise per-unit costs a lot.
- ryanmercer 8y ago
  >Houses built to the German Passivhaus standard would do just fine in Ohio. I used to live in Ohio and Western Pennsylvania, so I should know. There was one Minnesota church built with polystyrene panels that had to start running air conditioning in the middle of winter, the insulation was so good. You'd have to level most structures and rebuild from scratch to manage that in large parts of North America to make a difference. Never mind the fact heaters aren't the only thing that use electricity at night.
  - stcredzero 8y ago
    You'd have to level most structures and rebuild from scratch to manage that in large parts of North America to make a difference. New construction built like this is a good start. heaters aren't the only thing that use electricity at night Know your orders of magnitude. Resistive heating is just ridiculous. Heat exchangers are much better, but are like running Air Conditioners. In a passivhaus, my wife and I would be running a laptop, a clock, and the air filtration/exchanger, and that's it. Heating water is one of the big energy users, but Solar Water preheat based on heat pipes even works a treat in cloudy, chilly old England.
  - gascan 8y ago
    The biggest challenge probably being the 2x4 walls... if there's one code change to future-proof today's new housing stock, it might be adding 2 inches to the walls, either with 2x6 studs or 2 inches of rigid foam, for R-20 or so. Much of the rest is possible to retrofit, though not always easy. Actually, while we're on the subject, subslab insulation might be another.
- oconnore 8y ago
  It's a shame that there isn't the regulatory flexibility to subsidize desalination plants, because desalination plants are sort of like insurance policies in that you usually don't need them that much until a drought hits and then you really wish you had them. That sort of long term risk averse thinking is exactly where the market economy needs to be supplemented.
  - adventured 8y ago
    The market economy would charge the almond cartel and alfalfa growers a lot more money for their water abuse in California, which would instantly eliminate the water problems for the entire state. Versus allowing $10 billion of agriculture industry to hold a multi trillion dollar economy hostage.
    - thelastidiot 8y ago
      Let's add cannabis to the list which will use huge amount of water.
      - mikestew 8y ago
        Which plants use a lot of water is irrelevant to the discussion. Unless illegal cannabis growers in California were somehow having their water subsidized, which I do believe to be parent's main point.
  - Bricejm 8y ago
    Would it make sense to combine California's ability to produce solar and need for water? Build solar plants that run during the day that power desalination plants that fill reservoirs in the western mountainous area which then releases the water at night downhill to the main canal system while turning turbines on it's journey?
sf_rob 8y ago
You could probably invest in a thermal mass hybrid HVAC system e.g. use solar during the day to heat or cool a large thermal mass (thick interior concrete wall/floor to whatever temperature you need it to be at night.
- misterhtmlcss 8y ago
  Aren't they using molten salt for this? I think I heard about molten salt being used in a few cases for energy storage. Too bad I can't recall the details. Have you heard about this?
  - sf_rob 8y ago
    Oh sure, I more meant at the consumer level. At the production level molten salt is used to smooth out energy production rates at concentrated solar arrays. My understanding is that concentrated solar is no longer able to compete with photovoltaic production in most geographies.
- gm-conspiracy 8y ago
  Yes, this is a good idea, just expensive. There are both passive and active options. You need to drill pretty deep and have multiple wells, or have alot of land surface area and excavate (not too deep though). Other option is using water from a well or spring and dumping that water back into another well or stream (with an increase in water temp.).
- jpao79 8y ago
  Actually maybe a well insulated house could be considered a "thermal battery". If you look at the CAISO reports, a significant chunk of the duck curve is related to heating/cooling. If you had a super well insulated house, you could do the heating/cooling during the day. Instead today, people fire up the AC on overdrive when they get home in the evening to cool/heat the place down/up. What happens if your Nest could just fired it up at 3pm while the sun was still shining. In fact the opposite is done today to take advantage of early morning peak pricing, commercial buildings cool/heat at 3am to get optimal energy pricing. https://www.greentechmedia.com/articles/read/retired-cpuc-commissioner-takes-aim-at-caisos-duck-curve#gs.qKikfJ4 https://www.greentechmedia.com/articles/read/retired-cpuc-co...
overcast 8y ago
Why does it have to be electric heat? Natural Gas is doing a good job right now. Let's work on supplying electricity, for things that require electricity first. When we've moved away non renewable energy sources for electricity generation, then move onto the heating issues in colder climates.
- rb808 8y ago
  Yes Gas is great, but in 100 years it wont be cheap. I wasn't really talking about the next decade.
  - overcast 8y ago
    In a 100 years, at this rate there might not be any cold climates.
- wtetzner 8y ago
  But even with natural gas, don't you end up needing electricity to move the heat through the house?
  - organsnyder 8y ago
    Depends on the delivery mechanism. Our boiler (hot-water heat with radiators) has a pump that uses ~30 watts, and before we modernized our system it was entirely gravity-fed—hot water goes up to the living quarters, cold water comes back down to the basement. I haven't checked exactly, but I think our system uses around 100 watts total, and extracts 95% of the possible BTUs from the natural gas it consumes. The old system consumed basically nothing (just a bit to operate the thermostat controls), but was 80% efficient at best. Not surprisingly, forced air blowers consume more electricity—100-500 watts, according to my quick Googling.
  - rsynnott 8y ago
    Very little, generally. The pumps on a water-based radiator system are typically tiny.
ChuckMcM 8y ago
In my experience, the perception that "solar isn't for everybody", especially when using housing examples, is fooled by hidden assumptions that were made during the time. Consider the situation in 1950 when you are building a house, you can double or triple the cost of home construction by insulating it so that the net energy needed to heat or cool it is minimal, or you throw a oil burner in the basement which is burning fuel oil that costs a few cents per gallon and keep everything nice and toasty. The "obvious" choice there was not to spend the money on insulation but instead to just use really cheap energy to manage the temperature range. Makes everything much easier to engineer. If, on the other hand, you design with the assumption that energy is extremely expensive and so you minimize the need to use it to regulate temperatures within a house, you can design a house that is temperature stable with the minimal amount of energy input for air circulation. That gets you houses in the New Mexico desert that need no air conditioning (air cooling) and churches and office buildings in the northeast that need no additional heating. Things that I have read about include extended depth insulated exterior walls. "Smart" glass windows that reject 97% of the infrared and ultraviolet spectrum (I've got film on my house windows that are not that good but they do a tremendous job of minimizing heat load in the summer). Passive heat exchanger systems that keep the temperature balanced between upstairs and downstairs, and solar roof tiles that provide both insulation and energy for running the house. Does that help you if you're living in a 'mid century wood frame house', probably not. But it isn't that solar couldn't meet the heating and cooling needs, it is that combined with good house engineering this is already a solved problem.
- driverdan 8y ago
  > That gets you houses in the New Mexico desert that need no air conditioning (air cooling) and churches and office buildings in the northeast that need no additional heating. Do you have a source for your NM desert example? I'm doubtful you can keep a desert home cool with just airflow.
  - ChuckMcM 8y ago
    https://en.wikipedia.org/wiki/Earthship#Thermal_performance https://en.wikipedia.org/wiki/Earthship#Thermal_performance I've visited a couple of these places, they are pretty neat.
swebs 8y ago
We've built oil pipelines, why not "electricity pipelines" made of refrigerated, super conducting cable?
- epistasis 8y ago
  The technology that's being deployed right now for this is high-voltage DC: https://pv-magazine-usa.com/2018/07/09/eia-examines-hvdc-for-renewables/ https://pv-magazine-usa.com/2018/07/09/eia-examines-hvdc-for... It's an infrastructure investment that would pay dividends, but requires getting through a quagmire of politics.
- jankeymeulen 8y ago
  At 3% loss per 1000 km (625 miles) HVDC is already good enough I'd say.
- philipkglass 8y ago
  High voltage direct current lines can already cover vast distances. Siemens has started supplying equipment for a Chinese HVDC project that will transmit 12 gigawatts over 3300 kilometers: https://www.siemens.com/press/pool/de/pressemitteilungen/2017/energymanagement/PR2017110067EMEN.pdf https://www.siemens.com/press/pool/de/pressemitteilungen/201... That's a long enough line to stretch between California and East Coast states. Getting rights-of-way for big interstate transmission projects is harder than actually building the projects after those rights are secured. Superconducting cables can carry more power per cross section than HVDC lines, but they're a lot more expensive and immature. Nobody has yet found a project that would justify full-scale superconducting lines over more conventional high voltage lines built with ordinary resistive conductors.
rsynnott 8y ago
> If you live in Ohio heating in winter is a problem, solar isn't going to keep you warm on a cold night. (a) In any realistic scenarios where a grid goes mostly-solar, you'd expect that it would have adequate storage. (b) Storage heaters are a thing (and far more economical than batteries). (c) Modern "passive houses" and similar standards require surprisingly small energy input to heat, even when it's very cold outside. For whatever reason these mostly haven't been adopted in the US, but are becoming common in parts of Europe.
coryfklein 8y ago
We have a loooong way to go before cost of living in southern California is offsetting energy prices in Ohio.

by rb808 8y ago

stcredzero 8y ago

If you live in Ohio that is a problem, solar isn't going to keep you warm on a cold night Houses built to the German Passivhaus standard would do just fine in Ohio. I used to live in Ohio and Western Pennsylvania, so I should know. There was one Minnesota church built with polystyrene panels that had to start running air conditioning in the middle of winter, the insulation was so good. If you live in the South West though its perfect as Winter nights dont require much heat and the biggest loads are AC at the times when there is lots of sun. It can get pretty darn cold at night in the desert southwest. Again, insulation is the key. Of course water is the next problem, but cheap electricity can help that too. It's 10X as expensive to use techniques like desalinization. It's so much more expensive, that lots of desal plants get built, then get mothballed because it's that much cheaper to get water by other means.

sharkmerry 8y ago
is the expense of desalinization the electricity? Which would go down with adoption of solar?
- stcredzero 8y ago
  You also have to maintain equipment, but I think the electricity is the major thing.
- jerf 8y ago
  I imagine the idea is something more like one way to dump excessive solar capacity would be to desalinate water during the times of maximum power generation. Or perhaps I just steelmanned the argument.
- philipkglass 8y ago
  This is a decade old, but I think that the proportions are still about right: https://desline.com/Geneva/Banat.pdf https://desline.com/Geneva/Banat.pdf See the slide "Cost composition for a typical seawater RO (reverse osmosis) plant" Fixed charges (primarily capital cost): 31% Energy: 26% Maintenance and parts: 14% Membrane replacement: 13% Supervision and labor: 9% Chemicals: 7% Really cheap solar electricity could reduce the second largest expense (energy costs), but right now that's just an improvement for daylight hours. Battery-stored solar electricity is getting cheaper but it's not cheap enough to actually reduce nighttime desalination costs yet. And if you run the plant only during the day, you get less value out of the very largest expense (capital cost).
  - rsynnott 8y ago
    That's reverse osmosis. In a scenario where energy is very cheap (even if only for part of the day) there are other processes which require less maintenance, but more energy.
    - philipkglass 8y ago
      The previous slide in that presentation also shows a cost breakdown for a thermal process, multi-stage flash desalination. Fixed charges (primarily capital cost) 42% Energy 41% Maintenance and parts 8% Supervision and labor 7% Chemicals 2% Energy is nearly even with fixed costs for MSF, but fixed costs are even larger here. Leaving this type of plant idle between dusk and dawn would again raise per-unit costs a lot.
ryanmercer 8y ago
>Houses built to the German Passivhaus standard would do just fine in Ohio. I used to live in Ohio and Western Pennsylvania, so I should know. There was one Minnesota church built with polystyrene panels that had to start running air conditioning in the middle of winter, the insulation was so good. You'd have to level most structures and rebuild from scratch to manage that in large parts of North America to make a difference. Never mind the fact heaters aren't the only thing that use electricity at night.
- stcredzero 8y ago
  You'd have to level most structures and rebuild from scratch to manage that in large parts of North America to make a difference. New construction built like this is a good start. heaters aren't the only thing that use electricity at night Know your orders of magnitude. Resistive heating is just ridiculous. Heat exchangers are much better, but are like running Air Conditioners. In a passivhaus, my wife and I would be running a laptop, a clock, and the air filtration/exchanger, and that's it. Heating water is one of the big energy users, but Solar Water preheat based on heat pipes even works a treat in cloudy, chilly old England.
- gascan 8y ago
  The biggest challenge probably being the 2x4 walls... if there's one code change to future-proof today's new housing stock, it might be adding 2 inches to the walls, either with 2x6 studs or 2 inches of rigid foam, for R-20 or so. Much of the rest is possible to retrofit, though not always easy. Actually, while we're on the subject, subslab insulation might be another.
oconnore 8y ago
It's a shame that there isn't the regulatory flexibility to subsidize desalination plants, because desalination plants are sort of like insurance policies in that you usually don't need them that much until a drought hits and then you really wish you had them. That sort of long term risk averse thinking is exactly where the market economy needs to be supplemented.
- adventured 8y ago
  The market economy would charge the almond cartel and alfalfa growers a lot more money for their water abuse in California, which would instantly eliminate the water problems for the entire state. Versus allowing $10 billion of agriculture industry to hold a multi trillion dollar economy hostage.
  - thelastidiot 8y ago
    Let's add cannabis to the list which will use huge amount of water.
    - mikestew 8y ago
      Which plants use a lot of water is irrelevant to the discussion. Unless illegal cannabis growers in California were somehow having their water subsidized, which I do believe to be parent's main point.
- Bricejm 8y ago
  Would it make sense to combine California's ability to produce solar and need for water? Build solar plants that run during the day that power desalination plants that fill reservoirs in the western mountainous area which then releases the water at night downhill to the main canal system while turning turbines on it's journey?

sf_rob 8y ago

You could probably invest in a thermal mass hybrid HVAC system e.g. use solar during the day to heat or cool a large thermal mass (thick interior concrete wall/floor to whatever temperature you need it to be at night.

misterhtmlcss 8y ago
Aren't they using molten salt for this? I think I heard about molten salt being used in a few cases for energy storage. Too bad I can't recall the details. Have you heard about this?
- sf_rob 8y ago
  Oh sure, I more meant at the consumer level. At the production level molten salt is used to smooth out energy production rates at concentrated solar arrays. My understanding is that concentrated solar is no longer able to compete with photovoltaic production in most geographies.
gm-conspiracy 8y ago
Yes, this is a good idea, just expensive. There are both passive and active options. You need to drill pretty deep and have multiple wells, or have alot of land surface area and excavate (not too deep though). Other option is using water from a well or spring and dumping that water back into another well or stream (with an increase in water temp.).
jpao79 8y ago
Actually maybe a well insulated house could be considered a "thermal battery". If you look at the CAISO reports, a significant chunk of the duck curve is related to heating/cooling. If you had a super well insulated house, you could do the heating/cooling during the day. Instead today, people fire up the AC on overdrive when they get home in the evening to cool/heat the place down/up. What happens if your Nest could just fired it up at 3pm while the sun was still shining. In fact the opposite is done today to take advantage of early morning peak pricing, commercial buildings cool/heat at 3am to get optimal energy pricing. https://www.greentechmedia.com/articles/read/retired-cpuc-commissioner-takes-aim-at-caisos-duck-curve#gs.qKikfJ4 https://www.greentechmedia.com/articles/read/retired-cpuc-co...

overcast 8y ago

Why does it have to be electric heat? Natural Gas is doing a good job right now. Let's work on supplying electricity, for things that require electricity first. When we've moved away non renewable energy sources for electricity generation, then move onto the heating issues in colder climates.

rb808 8y ago
Yes Gas is great, but in 100 years it wont be cheap. I wasn't really talking about the next decade.
- overcast 8y ago
  In a 100 years, at this rate there might not be any cold climates.
wtetzner 8y ago
But even with natural gas, don't you end up needing electricity to move the heat through the house?
- organsnyder 8y ago
  Depends on the delivery mechanism. Our boiler (hot-water heat with radiators) has a pump that uses ~30 watts, and before we modernized our system it was entirely gravity-fed—hot water goes up to the living quarters, cold water comes back down to the basement. I haven't checked exactly, but I think our system uses around 100 watts total, and extracts 95% of the possible BTUs from the natural gas it consumes. The old system consumed basically nothing (just a bit to operate the thermostat controls), but was 80% efficient at best. Not surprisingly, forced air blowers consume more electricity—100-500 watts, according to my quick Googling.
- rsynnott 8y ago
  Very little, generally. The pumps on a water-based radiator system are typically tiny.

ChuckMcM 8y ago

In my experience, the perception that "solar isn't for everybody", especially when using housing examples, is fooled by hidden assumptions that were made during the time. Consider the situation in 1950 when you are building a house, you can double or triple the cost of home construction by insulating it so that the net energy needed to heat or cool it is minimal, or you throw a oil burner in the basement which is burning fuel oil that costs a few cents per gallon and keep everything nice and toasty. The "obvious" choice there was not to spend the money on insulation but instead to just use really cheap energy to manage the temperature range. Makes everything much easier to engineer. If, on the other hand, you design with the assumption that energy is extremely expensive and so you minimize the need to use it to regulate temperatures within a house, you can design a house that is temperature stable with the minimal amount of energy input for air circulation. That gets you houses in the New Mexico desert that need no air conditioning (air cooling) and churches and office buildings in the northeast that need no additional heating. Things that I have read about include extended depth insulated exterior walls. "Smart" glass windows that reject 97% of the infrared and ultraviolet spectrum (I've got film on my house windows that are not that good but they do a tremendous job of minimizing heat load in the summer). Passive heat exchanger systems that keep the temperature balanced between upstairs and downstairs, and solar roof tiles that provide both insulation and energy for running the house. Does that help you if you're living in a 'mid century wood frame house', probably not. But it isn't that solar couldn't meet the heating and cooling needs, it is that combined with good house engineering this is already a solved problem.

driverdan 8y ago
> That gets you houses in the New Mexico desert that need no air conditioning (air cooling) and churches and office buildings in the northeast that need no additional heating. Do you have a source for your NM desert example? I'm doubtful you can keep a desert home cool with just airflow.
- ChuckMcM 8y ago
  https://en.wikipedia.org/wiki/Earthship#Thermal_performance https://en.wikipedia.org/wiki/Earthship#Thermal_performance I've visited a couple of these places, they are pretty neat.

swebs 8y ago

We've built oil pipelines, why not "electricity pipelines" made of refrigerated, super conducting cable?

epistasis 8y ago
The technology that's being deployed right now for this is high-voltage DC: https://pv-magazine-usa.com/2018/07/09/eia-examines-hvdc-for-renewables/ https://pv-magazine-usa.com/2018/07/09/eia-examines-hvdc-for... It's an infrastructure investment that would pay dividends, but requires getting through a quagmire of politics.
jankeymeulen 8y ago
At 3% loss per 1000 km (625 miles) HVDC is already good enough I'd say.
philipkglass 8y ago
High voltage direct current lines can already cover vast distances. Siemens has started supplying equipment for a Chinese HVDC project that will transmit 12 gigawatts over 3300 kilometers: https://www.siemens.com/press/pool/de/pressemitteilungen/2017/energymanagement/PR2017110067EMEN.pdf https://www.siemens.com/press/pool/de/pressemitteilungen/201... That's a long enough line to stretch between California and East Coast states. Getting rights-of-way for big interstate transmission projects is harder than actually building the projects after those rights are secured. Superconducting cables can carry more power per cross section than HVDC lines, but they're a lot more expensive and immature. Nobody has yet found a project that would justify full-scale superconducting lines over more conventional high voltage lines built with ordinary resistive conductors.

rsynnott 8y ago

> If you live in Ohio heating in winter is a problem, solar isn't going to keep you warm on a cold night. (a) In any realistic scenarios where a grid goes mostly-solar, you'd expect that it would have adequate storage. (b) Storage heaters are a thing (and far more economical than batteries). (c) Modern "passive houses" and similar standards require surprisingly small energy input to heat, even when it's very cold outside. For whatever reason these mostly haven't been adopted in the US, but are becoming common in parts of Europe.

coryfklein 8y ago

We have a loooong way to go before cost of living in southern California is offsetting energy prices in Ohio.