Texas Power Outage Danger Until June 18th. Texans told to conserve energy!

[BenFranklin'sSpectacles + 762]

10 hours ago, nsdp said:

Well if you have ever looked at wind production curves?  Wind peaks in Jan and Feb at night.

And do they do this every night, on demand? If not, you need something on standby to fill their gaps.

[Eric Gagen + 713]

11 hours ago, Dan Clemmensen said:

By that measure, heat pumps are more than 100% efficient. They provide more heat than the BTU value of the NG that was used to produce the electricity that they use. They are called "heat pumps" for a reason: they concentrate the low-temperature heat in the outside air to produce high-temperature heat in the inside air. A ground-source heat pump is even more efficient than an air-source heat pump.

I didn't discuss heat pumps for a reason, and it was reason #1 - don't live somewhere outrageously cold.  The amount of heating needs I am willing to put up with are small enough that the capital cost of installing a heat pump probably aren't worth it when amortized over 20 years or so.  I'll admit that I haven't tried to price it out though, so I could be completely wrong.  At least in the climates I have lived in, annual heating costs for 2,500 - 3,000 ft^2 homes costs somewhere in the range of $200 a year or less.  In the place where we had a good fireplace with a heatilater and I had enough wood available to cut, it was effectively free (and I got a nice workout splitting the wood too!)

Edited June 20, 2021 by Eric Gagen

[Eric Gagen + 713]

9 hours ago, footeab@yahoo.com said:

If you installed a natural gas powered heat pump you would get 3X-->5X the heat and AC as well.  Of course at this point go electric and install a solar loop for the AC side of things. 

Still waiting for a residential heat pump that also has a loop tap for the hot water tank.  Maybe one exists.  Have to admit Have not looked for a normal heat pump  in 5 years. 

This discussion and my response was predicated on the assumption that solar electric power was already the primary means of power for the residence, and that the problem was finding ways to produce heating when the solar system was non functional, or functioning at a low level, so the air conditioning 'problem' is already covered.  

I could be wrong, but isn't the output temperature from heat pumps to low to be workable for hot water heating without some crazy expensive equipment?  

[Ward Smith + 6,615]

BTW, pumped storage only works with altitude so in flat Texas you're going to be challenged to find a location, let alone worry about your "lake" evaporating away

[Eric Gagen + 713]

7 minutes ago, Ward Smith said:

BTW, pumped storage only works with altitude so in flat Texas you're going to be challenged to find a location, let alone worry about your "lake" evaporating away

Completely agreed.  The entire discussion was completely hypothetical, so I didn't feel the need to let reality intrude.  In the case of Texas, of course it is correct that pumped storage is exceedingly limited in scope, and the places where it is viable are too far from population centers to be useful anyway.  

[Dan Clemmensen + 1,011]

7 hours ago, Eric Gagen said:

This discussion and my response was predicated on the assumption that solar electric power was already the primary means of power for the residence, and that the problem was finding ways to produce heating when the solar system was non functional, or functioning at a low level, so the air conditioning 'problem' is already covered.  

I could be wrong, but isn't the output temperature from heat pumps to low to be workable for hot water heating without some crazy expensive equipment?  

An integrated HVAC/hot-water heat pump system prpbably makes no sense, but  heat pump hot water heaters are now generally available and they do make a lot of sense. It pumps heat out of your house air and into the hot water, but that hot water will eventually heat your house up, so the net effect is very small.

https://www.homedepot.com/p/Rheem-Performance-Platinum-50-Gal-10-Year-Hybrid-High-Efficiency-Smart-Tank-Electric-Water-Heater-XE50T10H45U0/312742081?source=shoppingads&locale=en-US&mtc=Shopping-VF-F_DYNM-G-D26P-26_10_WATER_HEATERS-RHEEM-NA-Feed-SMART-2237722-WF-MK466033326_9016147011_FY21_2529&cm_mmc=Shopping-VF-F_DYNM-G-D26P-26_10_WATER_HEATERS-RHEEM-NA-Feed-SMART-2237722-WF-MK466033326_9016147011_FY21_2529-71700000084558371-58700007181517082-92700064485592735&gclid=CjwKCAjwzruGBhBAEiwAUqMR8I1euHIJINg075HtTtmD7Y_rsxg8eYWS20nfPGcowbnkIGnihQZk9hoC1JUQAvD_BwE&gclsrc=aw.ds

[Eric Gagen + 713]

1 hour ago, Dan Clemmensen said:

An integrated HVAC/hot-water heat pump system prpbably makes no sense, but  heat pump hot water heaters are now generally available and they do make a lot of sense. It pumps heat out of your house air and into the hot water, but that hot water will eventually heat your house up, so the net effect is very small.

https://www.homedepot.com/p/Rheem-Performance-Platinum-50-Gal-10-Year-Hybrid-High-Efficiency-Smart-Tank-Electric-Water-Heater-XE50T10H45U0/312742081?source=shoppingads&locale=en-US&mtc=Shopping-VF-F_DYNM-G-D26P-26_10_WATER_HEATERS-RHEEM-NA-Feed-SMART-2237722-WF-MK466033326_9016147011_FY21_2529&cm_mmc=Shopping-VF-F_DYNM-G-D26P-26_10_WATER_HEATERS-RHEEM-NA-Feed-SMART-2237722-WF-MK466033326_9016147011_FY21_2529-71700000084558371-58700007181517082-92700064485592735&gclid=CjwKCAjwzruGBhBAEiwAUqMR8I1euHIJINg075HtTtmD7Y_rsxg8eYWS20nfPGcowbnkIGnihQZk9hoC1JUQAvD_BwE&gclsrc=aw.ds

This actually proves my point with respect to the efficiency of a 'heat pump' hot water heater versus natural gas. It's not JUST a heat pump - you have to add direct electric heating to the system as well.  They claim a savings of up to $4,800 over 10 years when compared with a normal electric hot water hot water heater.  That's quite a claim, and would justify the $1,500 up front capital cost.  Now lets compare with a natural gas hot water heater.  I have a pair of 50 gallon natural gas hot water heaters in my house, and replacements cost $500 each (same brand and size as the ones I have now as per Home depot's site).  My natural gas bill in the summer time runs around $25 a month.  This also covers our gas stove, but for simplicity sake, lets assume that the whole bill comes only from the hot water heaters, so I am spending $300 a year on hot water for a direct heat natural gas system.  That works out to $3,000 over 10 years, plus $1,000 for initial purchase, for a total capex + opex of $4,000, and an average cost of ownership of $400 a year.  Lets compare to the Rheem heat pump high efficiency electric system.  I need $3,000 in capex, and the operating cost is ~ $100 a year per unit https://images.thdstatic.com/catalog/pdfImages/b0/b01175ac-8902-4aac-80bd-b3ba804e7b36.pdf (this is in fact about what I pay for electricity here) or $200 a year for both.   Over 10 years, the OPEX is $2,000.  Thus for the high efficiency model, my total cost of ownership for 10 years is $5,000 for an overage cost of ownership of $500 a year.  In theory,  IF the system were to stay perfectly functional, and efficient, it would pay for itself over the course of 40 years.  However no hot water heater lasts that long - if you are fortunate they make it for 20 years before they rust/corrode apart.  

QED:  If you don't have gas service to your home,  a heat pump hot water heater makes sense - it will save a lot of money.  If you have gas service, run away, because you are paying a lot more for a system which is too inefficient to pay for itself. All the extra metals, craftmanship, manufacturing costs, etc.  of the complex hot water heater destroy the operating cost savings if the fuel  to run a bunsen burner under a metal box are low enough.  

Edited June 20, 2021 by Eric Gagen

[Dan Clemmensen + 1,011]

5 minutes ago, Eric Gagen said:

This actually proves my point with respect to the efficiency of a 'heat pump' hot water heater versus natural gas. It's not JUST a heat pump - you have to add direct electric heating to the system as well.  They claim a savings of up to $4,800 over 10 years when compared with a normal electric hot water hot water heater.  That's quite a claim, and would justify the $1,500 up front capital cost.  Now lets compare with a natural gas hot water heater.  I have a pair of 50 gallon natural gas hot water heaters in my house, and replacements cost $500 each (same brand and size as the ones I have now as per Home depot's site).  My natural gas bill in the summer time runs around $25 a month.  This also covers our gas stove, but for simplicity sake, lets assume that the whole bill comes only from the hot water heaters, so I am spending $300 a year on hot water for a direct heat natural gas system.  That works out to $3,000 over 10 years, plus $1,000 for initial purchase, for a total capex + opex of $4,000, and an average cost of ownership of $400 a year.  Lets compare to the Rheem heat pump high efficiency electric system.  I need $3,000 in capex, and the operating cost is ~ $100 a year per unit https://images.thdstatic.com/catalog/pdfImages/b0/b01175ac-8902-4aac-80bd-b3ba804e7b36.pdf (this is in fact about what I pay for electricity here) or $200 a year for both.   Over 10 years, the OPEX is $2,000.  Thus for the high efficiency model, my total cost of ownership for 10 years is $5,000 for an overage cost of ownership of $500 a year.  In theory,  IF the system were to stay perfectly functional, and efficient, it would pay for itself over the course of 40 years.  However no hot water heater lasts that long - if you are fortunate they make it for 20 years before they rust/corrode apart.  

QED:  If you don't have gas service to your home,  a heat pump hot water heater makes sense - it will save a lot of money.  If you have gas service, run away, because you are paying a lot more for a system which is too inefficient to pay for itself. All the extra metals, craftmanship, manufacturing costs, etc.  of the complex hot water heater destroy the operating cost savings if the fuel  to run a bunsen burner under metal box are low enough.  

Agreed. If you have NG in your house already, it's hard to beat even when you give the heat pump system every advantage in your analysis. However, If you do not have NG, and most especially if you have solar PVs on the roof, then they make lots of sense. You can (at least in theory) store energy. Over-heat the water with excess solar PV, (using a tempering valve to maintain constant delivered temp), and allow the water to get cooler when you don't have excess solar PV.

The other possibility is a simple solar water heater, but with the cost of solar PV and batteries getting cheaper, the electrical system is more cost-effective because it is more flexible.

[Eric Gagen + 713]

17 minutes ago, Dan Clemmensen said:

Agreed. If you have NG in your house already, it's hard to beat even when you give the heat pump system every advantage in your analysis. However, If you do not have NG, and most especially if you have solar PVs on the roof, then they make lots of sense. You can (at least in theory) store energy. Over-heat the water with excess solar PV, (using a tempering valve to maintain constant delivered temp), and allow the water to get cooler when you don't have excess solar PV.

The other possibility is a simple solar water heater, but with the cost of solar PV and batteries getting cheaper, the electrical system is more cost-effective because it is more flexible.

My wife and I are planning to make a move to a more rural area once our youngest son graduates high school (about 3 years) Looking at current trends and directions in the world and economics means we intend to set up the following system wherever we land.   

1. Solar array with battery system sufficient to operate the house on a 24 hour basis
2. Ford F150 lightning with the large battery, to operate as a 'flex' backup, extending our average power system needs over 3-4 days instead of 24 hours.
3. Grid electric hookup
4. natural gas service (propane if we aren't on a NG grid)

Location is not yet determined - it depends on work, where our kids are at, and a host of other factors.  

I believe this will give us a very wide range of flexibility to take advantage of differential prices of electricity and insulate ourselves from grid problems at the lowest cost of ownership. We will have a vehicle that we can 'run for free' after the capex of the solar systems.  I believe in doing the right thing from the environmental perspective, and my job as a petroleum engineer isn't a reason to change that.  All that said,  I won't be an environmentalist if it means sweating like a pig in the dark, or eating fake meat.  Civilization means air conditioning, mechanized farming, steak, whiskey, internet, and HD TV.  It requires effort and I'm a fan of civilization, and I'll do my part to keep it going.    

Edited June 20, 2021 by Eric Gagen

[footeab@yahoo.com + 2,190]

10 hours ago, Eric Gagen said:

I could be wrong, but isn't the output temperature from heat pumps to low to be workable for hot water heating without some crazy expensive equipment?  

Nope. You can buy them today.  Use same refrigerant.  But NG is still cheaper I'll bet

[Eric Gagen + 713]

1 hour ago, footeab@yahoo.com said:

Nope. You can buy them today.  Use same refrigerant.  But NG is still cheaper I'll bet

Actually I'm assuming solar electric for air conditioning.  I honestly haven't looked at the heat pump situation very much, although as my reply to @Dan Clemmensen notes, it doesn't seem to work on an economic basis for water heating.  Maybe it works for air conditioning though?  

[footeab@yahoo.com + 2,190]

16 minutes ago, Eric Gagen said:

Actually I'm assuming solar electric for air conditioning.  I honestly haven't looked at the heat pump situation very much, although as my reply to @Dan Clemmensen notes, it doesn't seem to work on an economic basis for water heating.  Maybe it works for air conditioning though?  

It is a quantity issue really regarding solar.  How long do you wish to amoritize the initial cost?  For instance Solar thermal tied to a heat pump beats everything if you amortize the cost of the tanks with insulation over a long enough period of time for even small quantities of hot water.  THe more hot water you need the quicker the payback...

As for powering said heat pump... That requires batteries or using the grid or NG as the best time to run said heat pump for AC or heat is at night unless it is bitterly cold out and then you need a Geo theermal ground loop or geothermal well. 

[Eric Gagen + 713]

38 minutes ago, footeab@yahoo.com said:

It is a quantity issue really regarding solar.  How long do you wish to amoritize the initial cost?  For instance Solar thermal tied to a heat pump beats everything if you amortize the cost of the tanks with insulation over a long enough period of time for even small quantities of hot water.  THe more hot water you need the quicker the payback...

As for powering said heat pump... That requires batteries or using the grid or NG as the best time to run said heat pump for AC or heat is at night unless it is bitterly cold out and then you need a Geo theermal ground loop or geothermal well. 

For solar water heating, that's not what the data seems to indicate, as per my answer to dan clemmenson.  It only works if you assume that you are comparing it to an electrically operated conventional hot water heater.  Compared to a gas fired hot water heater it's obviously wasteful.  Air conditioning needs to run hardest in the mid day, and late afternoon, when solar output should be at or near maximum, and you aren't using anything but brute force - lots of sun = lots of electricity = cold air conditioning.  Of course you need a solid 24 hours of battery capacity to go with your solar system if you expect it to be even semi functional.  

[footeab@yahoo.com + 2,190]

4 hours ago, Eric Gagen said:

For solar water heating, that's not what the data seems to indicate, as per my answer to dan clemmenson.  It only works if you assume that you are comparing it to an electrically operated conventional hot water heater.  Compared to a gas fired hot water heater it's obviously wasteful.  Air conditioning needs to run hardest in the mid day, and late afternoon, when solar output should be at or near maximum, and you aren't using anything but brute force - lots of sun = lots of electricity = cold air conditioning.  Of course you need a solid 24 hours of battery capacity to go with your solar system if you expect it to be even semi functional.  

Not true, half AC load is after the sun goes down.  Thus if you want to use Solar, you have to use large insulated cold water storage tanks, or batteries. 

[Eric Gagen + 713]

5 hours ago, footeab@yahoo.com said:

Not true, half AC load is after the sun goes down.  Thus if you want to use Solar, you have to use large insulated cold water storage tanks, or batteries. 

I'll repeat, and bold my own post which you quoted, and apparently did not read: "Of course you need a solid 24 hours of battery capacity to go with your solar system if you expect it to be even semi functional."  Any solar energy array must have a robust battery storage system to be of any economic value.  I would assume that outside of some elderly legacy solar systems from the era when battery storage was not yet developed properly, or grid scale systems, that ALL small scale solar installations have a battery system as a part of them, with the only question being 'how big'. 

 

•  
• Quote
•  
• Edit

[Dan Clemmensen + 1,011]

19 hours ago, Eric Gagen said:

My wife and I are planning to make a move to a more rural area once our youngest son graduates high school (about 3 years) Looking at current trends and directions in the world and economics means we intend to set up the following system wherever we land.   

1. Solar array with battery system sufficient to operate the house on a 24 hour basis
2. Ford F150 lightning with the large battery, to operate as a 'flex' backup, extending our average power system needs over 3-4 days instead of 24 hours.
3. Grid electric hookup
4. natural gas service (propane if we aren't on a NG grid)

Location is not yet determined - it depends on work, where our kids are at, and a host of other factors.  

I believe this will give us a very wide range of flexibility to take advantage of differential prices of electricity and insulate ourselves from grid problems at the lowest cost of ownership. We will have a vehicle that we can 'run for free' after the capex of the solar systems.  I believe in doing the right thing from the environmental perspective, and my job as a petroleum engineer isn't a reason to change that.  All that said,  I won't be an environmentalist if it means sweating like a pig in the dark, or eating fake meat.  Civilization means air conditioning, mechanized farming, steak, whiskey, internet, and HD TV.  It requires effort and I'm a fan of civilization, and I'll do my part to keep it going.    

My fantasy retirement location would be 30 or more acres on the north (i.e., south-facing) slope of a fairly steep valley. House near the top designed to optimize the solar roof and maximize earth insulation. A one-acre pond with average depth of 10 feet near the top (10 acre-feet=3258510 gal), and another near the bottom, with a 100-meter vertical drop. 1000 gal at 100 meters is 1kWh, so the storage is 3258.5 kWh. De-rate by by .64 for 80% conversion efficiency each way: 2085 kWh. pump/turbine generator is 10 kW. It takes about 36 8-hour days to fill the top pond @ 10 kW and maybe 7 24-hour days to empty it at max, but you don't need 10 kW continuous. Clearly you don't need 10 acre-feet, but pond size is not a major cost consideration, so size depends more on available land. Ponds would be lined with EDPM pond liner, and covered, probably with heavy floating plastic. A smallish battery is used to stabilize the system. In my fantasy world the bottom pond is on or near a creek with at least a seasonal water supply, so you can draw the initial water supply "for free" and also draw any makeup water if you spring a leak. If your land is really steep, you get a 200-meter drop and double the storage capacity.

This system is inexpensive except for the capital and labor to build the ponds and the trench for the pipe and cables. I would buy a used tractor/backhoe/front-loader and spend a few months on that as a retirement project, and then sell the tractor.

Edited June 21, 2021 by Dan Clemmensen
cp

[ronwagn + 6,290]

On 6/19/2021 at 9:48 PM, footeab@yahoo.com said:

If you installed a natural gas powered heat pump you would get 3X-->5X the heat and AC as well.  Of course at this point go electric and install a solar loop for the AC side of things. 

Still waiting for a residential heat pump that also has a loop tap for the hot water tank.  Maybe one exists.  Have to admit Have not looked for a normal heat pump  in 5 years. 

They are fine in temperate areas but not for cold climates. https://www.cranburycomfort.com/benefits-limitations-heat-pumps/

[footeab@yahoo.com + 2,190]

2 hours ago, ronwagn said:

They are fine in temperate areas but not for cold climates. https://www.cranburycomfort.com/benefits-limitations-heat-pumps/

Not true at all. Just more expensive to install and can't be done by brain dead individuals.  Requires larger radiators for the icing problems for heat transfer, or you use geothermal ground loop/well. 

If one's standard is a rattlebox window heat pump, then the article is correct, but if all you do is switch out that tiny barely viable radiator in those things for one the size in your average car you can buy for less than $100 at NAPA, or go to your used car dealership and get a truck radiator which is 3X the size and costs half as much, for same amount of working fluid tonnage, then you gain about 10C, depending on where we are talking about.  Want another 10C?  Add another car sized radiator. 

The solution is absurdly cheap.  Every major building in Spokane/Chicago/Minneapolis or any other major city up north uses Heat pumps to heat/cool their buildings. The only reason some of them don't by now is that NG is absurdly cheap.  Of course the advanced commercial Heat pumps are dual Electric/NG powered so...

[Ecocharger + 1,470]

On 6/18/2021 at 5:38 PM, Jay McKinsey said:

HaHa you really stepped in it this time. Thanks for again showing us just how much you don't understand economics or how the grid works.

Pumped storage has been a critical mechanism for delivering lowest cost electricity for decades by allowing nuc and coal to run at an optimal constant rate 24/7 even though demand fluctuates every day between nighttime low and daytime peak.

You guys seem to miss the point on a regular basis. Natural gas is cheaper as a generator of backup electricity.

Only government intervention creates a high-cost system. 

[Ecocharger + 1,470]

On 6/20/2021 at 3:16 PM, Eric Gagen said:

Completely agreed.  The entire discussion was completely hypothetical, so I didn't feel the need to let reality intrude.  In the case of Texas, of course it is correct that pumped storage is exceedingly limited in scope, and the places where it is viable are too far from population centers to be useful anyway.  

It is always better to let reality intrude.

[Ecocharger + 1,470]

On 6/17/2021 at 12:41 AM, turbguy said:

Once it's stored, it is less cheap, but might still be profitable.

That is the perspective where we distinguish social and private considerations. Something can be profitable to the contracted producer, but still create a social cost compared to least cost production.

If you reduce the competing sources of energy production, there is usually a social cost.

[Jay McKinsey + 1,490]

23 minutes ago, Ecocharger said:

You guys seem to miss the point on a regular basis. Natural gas is cheaper as a generator of backup electricity.

Only government intervention creates a high-cost system. 

Another claim without evidence. How about you for once show up with actual numbers to back up your claims?

Edited June 22, 2021 by Jay McKinsey

[turbguy + 1,543]

40 minutes ago, Ecocharger said:

That is the perspective where we distinguish social and private considerations. Something can be profitable to the contracted producer, but still create a social cost compared to least cost production.

If you reduce the competing sources of energy production, there is usually a social cost.

What are the social costs you are considering when storing energy?

[Jay McKinsey + 1,490]

Battery costs are dropping fast. They are already beating Natural Gas peakers. 

"According to a recent analysis of global battery-storage projects by Bloomberg NEF, lithium ion batteries are now undercutting gas peaking plants in much of the world. At an all-in cost of $132/MWh, a four-hour utility scale battery is now priced below the global gas-peaker plant average at $173/MWh."

https://www.spglobal.com/platts/en/market-insights/latest-news/electric-power/060821-natural-gas-in-transition-batteries-target-grid-balancing-lithium-ion-costs-tumble

 

[turbguy + 1,543]

10 minutes ago, Jay McKinsey said:

Battery costs are dropping fast. They are already beating Natural Gas peakers. 

"According to a recent analysis of global battery-storage projects by Bloomberg NEF, lithium ion batteries are now undercutting gas peaking plants in much of the world. At an all-in cost of $132/MWh, a four-hour utility scale battery is now priced below the global gas-peaker plant average at $173/MWh."

https://www.spglobal.com/platts/en/market-insights/latest-news/electric-power/060821-natural-gas-in-transition-batteries-target-grid-balancing-lithium-ion-costs-tumble

 

Gee!

Where can I buy one of those batteries?

5 MWh would do me just fine at home!  Maybe even 1 MWh!

Edited June 23, 2021 by turbguy