Recent content by wxman

The confidence levels are seldom included in the discussion, especially "low confidence," which is why I emphasized that confidence level. By the way, the quotes are from IPCC Working Group 1 report.

Where did I say that, or even imply that?

According to the most recent IPCC Assessment Report (AR6), the following are its conclusions of current world climate conditions and notable changes since the start of the industrial revolution: Temperature Extremes... "It is virtually certain that hot extremes (including heatwaves) have...

I've been looking over the "Draft Regulatory Impact Assessment" to the Proposed Rule "Multi-Pollutant Emissions Standards for Model Years 2027 and Later Light-Duty and Medium-Duty Vehicles." It's quite obvious that we've reached diminishing returns with respect to criteria pollutants like...

Yes it can, up to 400,000 km.

There's a relatively new European vehicle life cycle called "carculator" (https://carculator.psi.ch/). There's an on-line version that free to use, just need to register. Based on this model, here are the the results using the default parameters: This appears to agree fairly well with the...

They're default "mid-size" passenger cars. "Lightweight materials" are those vehicles made with higher levels of e.g., aluminum and carbon fiber-reinforced plastic.

Sorry, I should have included the assumed useful life miles of the vehicles in my initial post. Here is a screen capture of the summary of emissions from vehicle manufacture of various vehicle technologies from GREET (GREET2):

There definitely is an environmental impact for any early replacement equipment. The life cycle for passenger cars in GREET is 173,151 miles (it's based on 15 year useful life at whatever the average miles/year are calculated by EPA). Not sure how replacement parts are handled in GREET. There...

I can hopefully clarify that graphic since it's mine. There are no units on the vertical axis since it's on a relative scale. I used Argonne National Laboratory's GREET model (https://greet.es.anl.gov/) to determine emission rates throughout the entire life cycle of the vehicles. The default...

Agree that manufacturing new vehicles uses a lot of resources and produces a lot of emissions. Here is a screen capture of emissions from manufacturing a new mid-sized passenger car from the latest version of the GREET model (GREET_2022):

The $3.50/gallon includes distribution costs and fuel taxes. Does that $0.02/kWh include distribution and taxes? If it does, why do residential consumers pay 6x or more than that? Why is the cost at public EV chargers as much as $0.43/kWh (Electrify America)? Biomass-based fuels are being...

Cost includes distribution and current state (average) and federal taxes on diesel fuel. Of course, any tax break for biomass-based diesel fuel would be that much less. The EPA analysis is based on a 50,000,000 gallon/year processing facility (33,200,000 gal/year biomass-based diesel fuel).

Aviation uses about 25B gallons/year of jet fuel. There's plenty more available for ground transportation (at least 35B gallons). The biomass fuels can be produced for less than $3.50/gallon, which is now much less than petroleum-based fuels, either diesel or gasoline. Where did you get those...

While I agree that long-distance freight should be moved to rail, I still disagree on the biofuels issue. There's not only a very significant supply of biomass sustainably available, there is a very urgent need for a market for much of it. The most important reason why wildfires are becoming...