ABG: U.S. carbon emissions spike in 2018 after years of falling

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I was kind of wondering if someone was confusing TWh with TW (generating capacity) and PWh (electricity usage), but was pushed for time and couldn't confirm, so glad someone did it. The U.S. generates a bit over 4 PWh/year of electricity from a bit over 1TW of generating capacity: https://en.wikipedia.org/wiki/Electricity_sector_of_the_United_States

That being said, the low capacity factor of VRE compared to the typical fossil-fueled plant means that generating capacity would have to increase by about 2.5 times for U.S. electricity to go completely renewable, plus all the new power transmission lines to get those renewables to the public, combined with cheap storage which doesn't yet exist (except in a few places where PHES will work). Smil and others have done the calcs, and IIRR it would take an expansion of land use for energy extraction. generation, transmission etc. at current RE power densities from about 0.5% of total U.S. land area to about 50.0% to go fully renewable (for all primary energy IIRC, not just electricity), which simply isn't realistic. Some improvements will take place in power density with PV and maybe some of the other RE techs (probably not wind), but nowhere near enough. Smil lists four major essential commodities for a modern world for which there is simply no viable renewably-produced option at the necessary mass scale at this time: cement, coke (for iron/steel production), ammonia (artificial fertilizer via Haber/Bosch process) and one other I forget.

On a more realistic level and talking about electricity, here's some room for optimism:
ICL model predicts lithium-ion batteries most competitive for storage applications by 2030
https://www.greencarcongress.com/2019/01/20190110-icl.html

Researchers at Imperial College London (ICL) developed a model to determine the lifetime costs (i.e., levelized cost)—as opposed to the investment cost—of 9 electricity storage technologies for 12 different applications between 2015 and 2050. The model predicts lithium-ion batteries to be the cheapest technology in the coming decades. An open-access paper on their work is published in the journal Joule.

The model, which incorporates data from more than 30 peer-reviewed studies, shows that at present, the cheapest energy storage mechanism is pumped-storage hydroelectricity, where water is pumped to a higher elevation with spare energy, then released to harvest the energy when needed.

However, as time progresses, pumped-storage hydroelectricity costs do not decrease, whereas lithium-ion battery costs come down, making them the cheapest option for most applications from 2030.

  • Personally, I was always quite skeptical toward lithium-ion storage for stationary applications, but when it comes to the levelized cost of storage—investment, operation and charging cost, technology lifetime, efficiency and performance degradation—lithium-ion combines decreasing cost with sufficient performance to dominate the majority of power system applications. I would have expected others to outperform in certain applications.

    —first author Oliver Schmidt

Schmidt adds that the model doesn’t say anything about whether lithium-ion batteries are the best-suited technology for stationary storage, but because it has such a head start in the market, it is best poised to be the cheapest option in the immediate future. The researchers can’t predict how new materials or advances will impact the market, but they hope their model, which is available open access to test a variety of technology cost and performance assumptions, can help industry and policymakers make informed investment decisions today.
Of course, a forecast is just that, and it ignores all the things ( such as resource limitations driving costs up) that can interfere with it coming true.
 
That being said, the low capacity factor of VRE compared to the typical fossil-fueled plant means that generating capacity would have to increase by about 2.5 times for U.S. electricity to go completely renewable, plus all the new power transmission lines to get those renewables to the public, combined with cheap storage which doesn't yet exist (except in a few places where PHES will work).

I think that all this focus on the national grid system is a big mistake. We need homes that are grid independent or semi-independent, local neighborhood grids, and city or county grids that can all stay up when the national system fails. A lot of that needed space for generation already exists on rooftops and in yards and farm fields. I'd love to have solar PV (or at least solar hot water for heating and plumbing) but our roofs are all slate, except for the shaded, badly-oriented garage.
 
LeftieBiker said:
That being said, the low capacity factor of VRE compared to the typical fossil-fueled plant means that generating capacity would have to increase by about 2.5 times for U.S. electricity to go completely renewable, plus all the new power transmission lines to get those renewables to the public, combined with cheap storage which doesn't yet exist (except in a few places where PHES will work).

I think that all this focus on the national grid system is a big mistake. We need homes that are grid independent or semi-independent, local neighborhood grids, and city or county grids that can all stay up when the national system fails. A lot of that needed space for generation already exists on rooftops and in yards and farm fields. I'd love to have solar PV (or at least solar hot water for heating and plumbing) but our roofs are all slate, except for the shaded, badly-oriented garage.

That would be good for you and me, bad for the government and semi monopolized utilities.
Just think, effectively 0 transmission losses, as opposed to putting them up in the middle of no where. In 2014 transmission losses accounted for about 10% or 11% of electricity used.
 
GRA said:
Smil and others have done the calcs, and IIRR it would take an expansion of land use for energy extraction. generation, transmission etc. at current RE power densities from about 0.5% of total U.S. land area to about 50.0% to go fully renewable (for all primary energy IIRC, not just electricity), which simply isn't realistic.
Thank you for this, GRA. There has been so much hand waving about converting to renewable sources by people who are completely ignorant of energy generation and usage.

BTW, is this the "Smil" that you referred to above? I may pick up a copy of that.

As discussed previously, some states are already at or near 100% electricity generation already due to hydropower, and some states such as Texas have the wind and sun resources (as well as massive amounts of "unused" land) to get to 100% electricity from "modern" renewable generators during the first half of this century. And they may be able to do it cost effectively.

But New York by 2040? Those New Yorkers will certainly pay a lot of tax to pay for the ignorance of their politicians. But they won't have 100% renewable electricity by 2040. (Yes, that is my prediction.)

And then there is all the other energy besides electricity that is consumed, as you point out. That's the bigger part of the pie and will only get addressed once we make real progress with electricity (which hasn't happened, yet).

Oilpan4 also makes an important point above:
Oilpan4 said:
LeftieBiker said:
I think that all this focus on the national grid system is a big mistake. We need homes that are grid independent or semi-independent, local neighborhood grids, and city or county grids that can all stay up when the national system fails. A lot of that needed space for generation already exists on rooftops and in yards and farm fields. I'd love to have solar PV (or at least solar hot water for heating and plumbing) but our roofs are all slate, except for the shaded, badly-oriented garage.
That would be good for you and me, bad for the government and semi monopolized utilities.
In many areas, through the magic (read: subsidy) of net metering, homeowners like me can generate all of their own electricity for BOTH transportation AND normal electrical applications using existing technologies. And, like GRA's reference above to Li-ion battery progress indicates, homeowners (and many smaller or low-energy businesses) may soon have the option to depart the grid at a comparable cost to what they pay today. That has several important effects on this issue:

1) Utilities see the writing on the wall with their residential and small-business customers. They know what is happening to other utilities such as wired telephone service: customers are "pulling the plug" at an increasing rate. As an example, when we purchased our home in 1998, we had the following monthly utility expenses: $125 for electricity, $30 for gasoline, $30 for landline telephone, and $75 for internet. That is a total of $260/month. Today? $20 for electricity, $20 for gasoline, $40 for cellular telephone and internet. Now our total is $80 or a total reduction of $180/month. The cellular carrier is the only one which has grown its business during that period. Sure, I paid for the electricity up-front by purchasing a PV system, but the utilities did not get that money.

2) Just as has happened to the remaining landline customers out there, the remaining electricity customers will begin experiencing higher rates. Ultimately, only the large electricity customers will remain, meaning they will eventually bear the entire costs of the system.

3) Many individuals in net-metering environments see that they can purchase a system to meet all of their personal energy needs and they extrapolate that ability to the entire country. Unfortunately, many of those are ignorant of the massive benefits that net metering affords in terms of time-shifting, the extreme differences in the ability of people in different regions to use renewable energy, the massive amounts of energy used for non-electricity applications today, and the massive amount of energy used by industry. That makes their ill-conceived extrapolation anything but accurate.

Yes, there will be an energy transition going forward. But it will happen at different rates in different locations. Unfortunately there are a lot of ignorant politicians out there who are going to drive many of their constituents into energy poverty in an effort to force this transition to occur in WAY too short of a period of time.
 
GRA said:
That being said, the low capacity factor of VRE compared to the typical fossil-fueled plant means that generating capacity would have to increase by about 2.5 times for U.S. electricity to go completely renewable, plus all the new power transmission lines to get those renewables to the public, combined with cheap storage which doesn't yet exist (except in a few places where PHES will work). Smil and others have done the calcs, and IIRR it would take an expansion of land use for energy extraction. generation, transmission etc. at current RE power densities from about 0.5% of total U.S. land area to about 50.0% to go fully renewable (for all primary energy IIRC, not just electricity), which simply isn't realistic.
That 50% land use figure is nonsensical. Can't you google a little and do trivial arithmetic ?!

I showed earlier in this thread that it will take ~ 2 TW to replace the fossils currently used in the US for electricity and transport.
Half of that can be rooftop, so 1 TW new land use.

Arithmetic (a lost art):

1.6 meter squared per kW http://www.suncyclopedia.com/en/area-required-for-solar-pv-power-plants/
2*10^9*1.6 = 3.2 * 10^9 square meters
US land area: ~ 4 million square miles = 10^13 square meters

That is before we consider conservation, improvements in panel efficiency, and off-shore wind production

----
But maybe the arithmetic is wrong ? Lets try some simple per capita numbers:
US population: 325 million
US land mass: 10 * 10^12 square meters
Land mass per capita: ~ 3 * 10^4 square meters
1% land use ? 300 square meters per capita.
My household uses under 3 square meters per capita to cover electricity and personal transport. I could triple my generation by adding panels to the roof.

---
Why not -- another simple exercise:
Panel efficiency of 20%
Utility scale capacity factor of 25%
Insolation of 1000 watts per meter*meter
-> 50 watts per meter*meter = 50*365*24 Wh a year per square meter PV = 438 kWh per year per square meter
Current US electricity generation from fossils is ~ 2.5 * 10^12 kWh a year
5.7* 10^9 square meters. If half is rooftop then ~ 2.85 * 10^9 square meters of 10^13 US land mass ... before accounting for wind, both on and off-shore.
----

Come on !
 
That being said, the low capacity factor of VRE compared to the typical fossil-fueled plant means that generating capacity would have to increase by about 2.5 times for U.S. electricity to go completely renewable.

Average capacity factor (CF) of utility fossils is ~ 50%
Current day utility installed large scale PV is ~ 25%
Current day on-shore wind is ~ 40%
Current day off-shore wind is ~ 55%

You can play with weighting as you see fit but if we figure 1/3 of each VRE resource then the average CF is 40% and 1.25x of current fossil capacity would be required. Bump it up to 1.5x just to say we are conservative, and we think that panel efficiency will never improve. :oops:
 
Don’t see the utilities going away; their roles may get more complicated. It may look scary for them now with PV solar, but we still need them on several accounts even for net delivery of electricity which may become greater in the next 20 years.

PV home solar will almost never be enough in winter and of course at night. Battery storage can help with time shifting at night but unless a massive amount of money is committed to home batteries this will still be a problem in the winter.

The household average for cars is over two, so as more vehicles go electric the demand on the grid for delivery will increase.

The bigger hit may come if/when houses convert from fossil fuel furnaces to heat pumps and natural gas water heating to heat pumps. A large percent in the US use more energy to heat their home air/water than they do for the rest of their electrical home needs.
 
SageBrush said:
I showed earlier in this thread that it will take ~ 2 TW to replace the fossils currently used in the US for electricity and transport.!
It seems you've missed a decimal point somewhere. We have 1 TW operating at 50% capacity factor (average) *today* to meet JUST the electricity needs of this country. 2 TW of renewables operating at 25% capacity factor (average) would *theoretically* meet these same needs. But not really, since renewable energy is not dispatchable, so even more, likely *much* more, is needed just to meet the electricity needs.

My PV generation is seasonally offset by about six months from my load. Think about electric space heating in December, January, and February.

Then there is the much larger part of the pie, which is all the other uses for fossil fuels, many of which cannot be met with renewables as GRA has details and many which will not be met by renewables in our lifetimes (regardless of when any of us were born).
 
iPlug said:
Don’t see the utilities going away; their roles may get more complicated. It may look scary for them now with PV solar, but we still need them on several accounts even for net delivery of electricity which may become greater in the next 20 years.
Sorry, I didn't mean to imply that they would go away. I said that with net metering their paying customers would be reduced to the larger customers who had no other alternative.

More likely net metering goes away first, just like it did in Nevada.
 
Got it.

But I think that even in a scenario with net metering being allowed to continue for residential customers, few people would be able to go net zero with home solar and heat pump air and water heating and 2 electric vehicles. For those in cold winter climates, the heat pumps will sometimes need to dip into backup resistance heating which will require even more electricity.

In this scenario, paying residential customers could increase.

Agree, a lot of this would be regionally variable based on climate and renewable resources available to that area.
 
RegGuheert said:
SageBrush said:
I showed earlier in this thread that it will take ~ 2 TW to replace the fossils currently used in the US for electricity and transport.!
It seems you've missed a decimal point somewhere. We have 1 TW operating at 50% capacity factor (average) *today* to meet JUST the electricity needs of this country. 2 TW of renewables operating at 25% capacity factor (average) would *theoretically* meet these same needs. But not really, since renewable energy is not dispatchable, so even more, likely *much* more, is needed just to meet the electricity needs.

My PV generation is seasonally offset by about six months from my load. Think about electric space heating in December, January, and February.

Then there is the much larger part of the pie, which is all the other uses for fossil fuels, many of which cannot be met with renewables as GRA has details and many which will not be met by renewables in our lifetimes (regardless of when any of us were born).

2017: https://www.eia.gov/tools/faqs/faq.php?id=427&t=3
electricity supplied by NG and coal: 2.5 * 10^12 kWh
One watt STC = 2.5 kWh per year generation
= 1 TW PV

Oil used in transport, 2017: https://www.eia.gov/tools/faqs/faq.php?id=427&t=3
20 million barrels a day, 42 gallons a barrel, 33 kWh a gallon, figure 20% efficiency:
Per year then: 365* 2 * 10^7 * 42 * 33 * 0.2 = 2.0 * 10^12 kWh
Electricity replacement: 0.8 TW
 
SageBrush said:
2017: https://www.eia.gov/tools/faqs/faq.php?id=427&t=3
electricity supplied by NG and coal: 2.5 * 10^12 kWh
One watt STC = 2.5 kWh per year generation
= 1 TW PV
Nothing ever got built successfully using unrealistic assumptions.

My nearly-ideally-pointed system produced about 1.3 kWh per watt STC last year at 39 degrees North latitude. As you go north, the numbers get worse and the differential between summer and wintertime production gets higher. Plus you need more energy in wintertime.

Many systems in the Seattle area produce about 6X as much electricity in June as they do in December.

You haven't accounted for shifting ANY energy from daytime to nighttime nor any energy from summertime to wintertime.

Simply put, PV gets much less viable as you move away from the equator.
SageBrush said:
Oil used in transport, 2017: https://www.eia.gov/tools/faqs/faq.php?id=427&t=3
20 million barrels a day, 42 gallons a barrel, 33 kWh a gallon, figure 20% efficiency:
Per year then: 365* 2 * 10^7 * 42 * 33 * 0.2 = 2.0 * 10^12 kWh
Electricity replacement: 0.8 TW
More optimistic assumptions. Oil is 20% efficient, electricity is 100% efficient and can be used exactly when it is produced.

Now, let's talk about what GRA was posting about before: total replacement of fossil fuels in the U.S., which came to about 80% of 59 quadrillion btus in 2018, or about 13.8 PWh. At 25% capacity factor with ALL generation done exactly when needed, that comes to 6.3 TW of renewable generation. Efficiency gains *might* get that down to about 4 TW of renewable generation. But the fact that renewable generators do not generate when you need them to, particularly seasonally, then the number likely needs to 3X to 6X higher.

That means approximately 12 TW to 24 TW of renewable generation in the U.S. to replace all fossil fuels.

But we haven't yet solved the storage problem. Simply put, this transition will take a long time.

All that said, I come up with a PV area of only about 12,000 km^2, or about 3% of the area of the continental U.S.. It is a very significant amount of area, but I don't see it getting to 50% unless the author in GRA's reference is talking about lots of wind farms or biofuel. Perhaps he is.
 
FWIW at our home in Rocklin, CA (same latitude as St. Louis, but sunnier) we generate 1.4 kWh per watt annually. 40% of our system (by watt potential generation) is facing directly NW so not favorable and winter yields there are markedly worse than the other panels. The rest of the system is facing SW or SE.

With the most efficient heat pump water heater we use 1400 kWh/yr, most of that in winter, of course.

With the most efficient ducted air sourced heat pump we used 1258 kWh for AC last summer. Only had the unit since last spring but have used 870 kWh thus far this winter. Cold season is half way done so expect this number to roughly double by the end of the cold season.

Our climate is warmer than most of the United States and still we are using more energy to heat our home and water in the winter than cool it in the summer.
 
RegGuheert said:
Nothing ever got built successfully using unrealistic assumptions.
How about data from what was actually built ?
https://emp.lbl.gov/utility-scale-solar
---

Regarding land use,
This estimate from 2008 (!) calculated 0.6% of US land mass or 22% of urban land area (aka rooftop.)
Panel efficiency has probably increased 50% since then.
https://atb.nrel.gov/electricity/2018/index.html?t=su
 
They know what is happening to other utilities such as wired telephone service: customers are "pulling the plug" at an increasing rate. As an example, when we purchased our home in 1998, we had the following monthly utility expenses: $125 for electricity, $30 for gasoline, $30 for landline telephone, and $75 for internet. That is a total of $260/month. Today? $20 for electricity, $20 for gasoline, $40 for cellular telephone and internet.

Wired phone utilities have been raising rates and cutting services for decades, in an apparent effort to drive people away from that utility, and into the more profitable cellular services. This isn't the same as people walking away while the wired phone service companies beg them to stay.

Our climate is warmer than most of the United States and still we are using more energy to heat our home and water in the winter than cool it in the summer.

This is simple physics. It will always take much less energy to just move heat than it does to create it using electricity. Unless heat pumps are developed that can move large amounts of heat at very low temps (a large blower would probably be required for this) it will always be harder and costlier to heat with air source heat pumps than with ground source units.
 
LeftieBiker said:
Unless heat pumps are developed that can move large amounts of heat at very low temps (a large blower would probably be required for this) it will always be harder and costlier to heat with air source heat pumps than with ground source units.
Not even close.

Ignoring technical obstacles for a moment like the gas used in the compressor and just focusing on efficiency differences, you have to calculate using a kelvin scale. The inefficiency that accrues from using ambient air temp as the source rather than ground is easily offset by the differences in cost installation, of which some of savings is plowed into improving the building envelope.
 
LeftieBiker said:
This is simple physics. It will always take much less energy to just move heat than it does to create it using electricity.

Agree in certain circumstances. Ground source heat pumps generally make sense in climates colder than ours. But outside of new construction and/or generous real estate, it’s often too costly for existing units.
 
iPlug said:
LeftieBiker said:
This is simple physics. It will always take much less energy to just move heat than it does to create it using electricity.

Agree in certain circumstances. Ground source heat pumps generally make sense in climates colder than ours. But outside of new construction and/or generous real estate, it’s often too costly for existing units.

Yes, that's what I'm struggling with. The long-term payback should more than cover the cost with state rebates applied, but it will be better as prices fall with more installations.
 
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