Texas EV Tax: Please Comment

A 90% efficient natural gas furnace delivers about 7,500 BTU per 1 lb. CO2 emissions. California's night-time energy mix (about the only time heat is called upon in the state) is around 3.2 lbs./CO2 per kWh. To match natural gas furnace emissions an electrically powered heat source in California would have to put out around 25,000 BTU/kWh after accounting for California's 6% transmission and distribution losses. In HVAC terms a 5-ton unit would have to run at around 2.4 kW. As far as I know we're not there yet.

Of course, a region's energy mix and time of use can dramatically change these numbers. California's day time energy mix has a lot more solar and wind, which brings CO2 emissions down to around 1.6 lbs. CO2/kWh. In places with those kinds of numbers when heat is called for a 5-ton unit drawing 4.8kW would match the emissions of a natural gas furnace.

 

They're bulldozing endangered desert tortoise habitat out here to build solar plants, and I'm sure they're not being charged more for the land than oil and gas leases are charged.

 

This is where keeping copies of my utility bills for the last 20 years comes in handy. In 2004 I was paying $0.1197/kWh after all taxes and fees. Today, from the same utility I am paying $0.247/kWh. That's an annualized growth rate of 4.36%. At the same time natural gas was $1.02 per hundred cubic feet and today it's $1.59 per hundred cubic feet - an annualized 2.66% growth rate.

 

Well... you're talking about history and I'm talking about the future. Not the same thing at all. Yes, one influences and informs the other but we're technically talking about two different subjects now.

I wholeheartedly agree with your point that gas furnace heat has been an excellent economic choice for Californians over the past 20 years.*

I just don't think it's going to be as good of a choice going forward. I can't predict with enough granularity to say electric will be the hands-down, miles-ahead winner.

I think it is important to realize that the landscape changes dramatically even if the gas/electric choice is only pulled to cost equivalence, never mind an inversion of the status quo.

*offer not valid in Porter Ranch

 

Lease rates for solar project are in the range of $300 to $2000 an acre, which includes ones on private land.
What's the average solar farm lease rate? | Strategic Solar Group

The BLM has a rent schedule that varies by the land's value and zone. In 2020, it ranges from $17.48 to $58,470.84 an acre.
Acreage Rent and Megawatt Capacity Fees (Years 2016-2021) for Solar and Wind Energy ROW Grants and Leases | Bureau of Land Management
https://www.blm.gov/sites/blm.gov/files/policies/IM%202017-096%20Attachment%201%20Solar%20Energy%20Acreage%20Rent%20and%20MW%20Capacity%20Fee%20Schedules_0.pdf

With land leases for oil and gas wells, there is first a bonus bid to buy the least. Some auctions have gone as high as $10,000 an acre, but most high bids are in the hundreds. Yet most go for the minimum bid of just $2 an acre. The average is under $20. The rental rate after that is $1.50 an acre for the first 5 years, and then $2 after that.
Federal Oil and Gas Royalty and Revenue Reform - Center for American Progress

 

Don't forget that the BLM collects 12.5% of all revenue generated by the oil and gas site in addition to the "rent."

The EIA says there were 491,205 natural gas wells in the US in 2019 (It's an interesting side not to me that this is basically a return to the pre-Obama levels, which were 493,100 in 2009, peaking at 586,213 in 2014, because it contrasts with the picture painted in the media of an out of control administration opening the flood gates for oil and gas leases. Maybe it's offset by a larger increase in oil wells? Haven't looked into it yet.).

EIA also says natural gas production in the US was about 36,515,188 million cubic feet in 2019, which works out to an average of 74 million cubic feet per well. 2019 wholesale natural gas prices were $2,570 per million cubic feet. That means each well averaged $190,000 worth of production, which would result in a $23,750 payment to BLM. You have to add that to the "rent" to get a final total of what's being paid for those leases.

 

How is that significant? If it's a skim of revenue, wouldn't every lessor pay the same percentage of revenue regardless of what they're doing on the land?

The delta between the "rent" petro extractors are allowed to pay vs. what renewable operators are stuck paying is a much bigger deal.

 

And renewable energy has fees per MW on federal land.

 

I don't know the details of oil and gas leases in terms of what's required to be leased. Do you have to lease just the surface area needed for your well equipment, or do you have to lease some acreage based upon what your extracting? If it's just the well head area then it would be comparable to PV plants in terms of environmental devastation directly caused by the lease. If you have to lease a bunch of acreage to cover mineral rights underneath, then I'd say acre-for-acre the PV plants are far more devastating since they bulldoze the entire site to bare earth, and they're often thousands of contiguous acres instead of of a patchwork (which is ugly, but still less impact on wildlife).

 

Ivanpah has a 377 MW nameplate rating and is producing 856,000 MWh annually. So they're paying $1.66 per MWh, which amounts to about 4% of the wholesale price. I'd say they're getting a pretty good deal compared to oil and gas at 12.5%.

 

That's okay, I don't think it's terribly important just now. The only reason we were talking about leases at all is because the oil industry has gotten awfully good at leasing lots of land for very, very little money compared to what everyone else is paying.

I think it's pretty likely that this style of subsidy will go away in the near future.

Oil and gas companies will shrug and pass the new rent costs on to consumers, just like the solar and wind guys have had to.

So, I have the expectation that gas and oil bills will rise.

Now, because some gas and oil is used to create electricity, I expect electrical rates to also rise. But, because some electricity is made other ways, the price of electricity is not likely to rise as fast as the cost of gas and oil.

I do think gas and oil will still look cheap for years to come. Families can still save money burning it for now, but that won't always be so.

 

Sources please? Those numbers seem very seriously whacked. Even coal is only 2.2 lbs_CO2/kWh, and California has only 3% coal.

Here are some figures I'm finding:
PG&E (undated, maybe old):
"3. PG&E Carbon Dioxide (CO2) Emissions Rates
– Electric: 0.524 lbs CO2 per kWh"

Average Californian (according to footnote, EPA-2007):
"–California Emissions Rate for Delivered Electricity: 0.879 lbs CO2 per kWh"

EIA- California Electricity Profile 2019:
"Net generation (megawatthours) 201,784,204 "
"Emissions - Carbon dioxide (thousand metric tons) 40,874"

My arithmetic of those, with units translation, comes to 0.446 lbs_CO2/kWh.

California's current consumption and emissions right now, as I type this tonight (late Sunday evening):

That 0.296 mTCO2/MWh translates to 0.653 lbs-CO2-equivalent/kWh.

That "equivalent" means that it includes the "global warning potential" of not just the CO2 emissions, but also of the associated CH4 and N2O emissions.


Based on this major disconnect between PiPLA's CO2/kWh claims vs what I'm seeing documented elsewhere, I won't bother even looking at his derivations for what heat pumps should do.

 

You are correct that there is a mathematical error caused by a transposition in a spreadsheet formula. I'm not afraid to admit it. Trying to do all these off the cuff calcs fast while doing other chores causes errors sometimes. The sources were:

June 19, 2021 supply at 05:00: 24,352 MW
June 19, 2021 emissions at 05:00: 8,177 mTCO2/h

Both figures are 5-minute averages and "hour-ized." That's 0.336 mTCO2 per MWh, or 741 lbs per MWh (0.741 lbs/kWh).

It changes them as follows:

To beat a 90% efficient natural gas furnace on CO2 emissions (1.17 lbsCO2/10 kBTU), a heat pump running on electricity described above will need to exceed 1.58 kWh/10 kBTU. Any modern heat pump in California's climate should be able to exceed those numbers.

Cost-wise, a 5-ton unit would consumes approximately 1 kWh per 12,000 BTU, or 8.333 kWh for 1 therm of natural gas heating. 8.333 kWh costs an average of $1.89 in California vs. $1.55 for natural gas ... a 22% difference.

You guys convinced me to look into a heat pump when it's the end of the economic life of my HVAC system.

 

A 5 ton unit will likely be a central unit, not a ductless minisplit. Central units generally lag minisplits a bit in efficiency scores, and I don't know if centrals are up to HSPF 12 just yet. Give them a few more years.

Is that 5 ton rating driven by cooling needs, not heating? For a climate that never gets below 28F, that sounds quite large ...

 

For cooling. 5 tons can barely keep up when temps are over 100. It has to run >50% duty cycle to keep temps around 76. I'd hate to see the place with no insulation. When I have to replace the unit I'll probably get something with a little more cooling capability.

 

I'm seeing natural gas listed as 117.0 lbs_CO2/MBTU. If my figuring is correct, that translates to 1.17 lbs/10,000BTU or 0.40 lbs/kWh-thermal. That is what a theoretical 100% furnace would deliver. Considering that the best natural gas furnaces are already running at 97%, It seems we can just use those theoretical numbers without adjustment and still be on target.

The best natural gas combined cycle plants (CCGT) are running in the mid-60%. 64% according to wikipedia, 68% claimed elsewhere. But a few years back, I was seeing a listing of plenty of new plants in China running at about 60%, but considerably fewer in the U.S. where the inventory was dominated by older technology plants, and others not pushing the latest efficiency envelope for various reasons.

For this exercise, I'll assign 60% to reasonable CCGT plants, which then means 0.67 lbs/kWh-electric. The quoted EIA page shows 0.91 lbs/kWh-electric, suggesting that the U.S. plants are averaging closer to 45% efficiency. We should up our game with more advanced plants

Heat pumps in heating modes (as opposed to cooling) are rated on an HSPF scale, for average performance over a weighted range of outside temperatures. Simple electric resistance heaters have a fixed HPSF score of 3.412. My ductless minisplit is rated 10.0, which means its reference-season average output is 2.93x that of electric heat. Leadfoot's much newer 3.6x unit would score an HPSF of about 12.3, or thereabouts if he rounded.

Driving these units from a 60% CCGT electric source would correspond to 0.23 lbs_CO2/kWH-thermal for an HSPF=10 unit, or 0.19 lbs for an HSPF=12 unit, a significant improvement over the 0.40 lbs for the best natural gas furnaces.

But with the current U.S. mix of natural gas generators, those figures rise to 0.31 lbs (HSPF=10) and 0.25 lbs (HSPF=12). Still better than any home natural gas furnace, but less compellingly so, unless comparing against cheaper 80% AFUE furnaces (0.50 lbs).

Because heat pumps work better in warmer outside conditions, they should perform somewhat better than this in California, somewhat worse in the upper MidWest.

 

How do heat pumps perform in cooling mode in comparison to a standard air conditioning unit of reasonable efficiency? If there's a performance difference, that has to be accounted for as well to make a full accounting of the impact of switching.

My unit is 15 SEER and in the hottest months I've used up to 900 kWh over my winter electrical usage with the thermostat set to 77°F. Those 100+ days with 80+ overnight lows can be a doozy.

 

Virtually all heat pumps also work for cooling, but have separate SEER ratings for that. Mine is rated for a SEER of 20. Slightly higher SEERs were available then, and best scores have climbed since.

Different models have different SEER / HSPF ratios, so don't take my ratio as universal, go look at the available products.

Just as with heating, ducted central units don't score quite as efficient as ductless zoned units. And higher capacity units usually don't score quite as well as small to medium units. I'm guessing that their heat exchangers are not proportionately enlarged, so they are dealing with greater temperature gradients and air handling backpressures.

With modern products now using inverters driving variable speed compressors and fans, the phrase "duty cycle" just seems so archaic. Instead of cycling on and off, these newer products will run continuously at lower (quieter) speeds and powers, which helps efficiency by reducing exchanger temperature gradients and airflow backpressures.

5 tons => 60,000 BTU/hr => 17.6 kW. At >50% duty cycle, that is more than 9 kW-thermal. My first reaction is "Ouch!', but then I've never lived in a cooling-dominant climate, so am really not in touch with the needs of living in such places. A recent news article indicates that only 34% of dwelling units here have air cooling. The next lowest major metro areas were SF at 36%, and Portland OR at 70%. Lots of hot places exceeded 99%.

I have AC only because it is an additional feature of the heat pump, which displaces most of my original electric resistance heating. By luck, it was installed shortly before nearby Seattle recorded its very first ever 'official' 100 degree day. We really needed it just 3 days of that heat streak, but happily made use of it for a full week. We 'needed' it only some summers then, not all. And now after making several improvements to the building envelope and in how we manage 'hot' spells, we don't 'need' it at all most summers, but turn it on occasionally just to exercise that side of the equipment.

I could detail what changes I made to reduce summer heat infiltration and solar heat gains. But many are specific to my particular house circumstances. For people living in actual hot climates, these steps alone won't be anywhere close to sufficient, but might help reduce some energy bills.

 

We're already with the low-E double-pane windows, shaded south-side of the house, and light-colored paint. The home was built with mostly no attic and R-19 (I assume based on thickness) ceiling insulation. The walls have ~R-13 insulation. I do have a problem with air leakage. Whenever the HVAC fan is running it sucks air from the outside. I have had two alleged HVAC techs here from two different companies and they both alleged that it's normal and tried to educate me that the air blowing out of the vents has to come from somewhere

 

Do you have a dedicated fresh air return?
That typically eliminates that issue.
In my area (heating is an issue, cooling is secondary) I believe a fresh air return has been part of the building code for a couple decades. Each regional climate will vary.