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Comment Re:Headline is stupid (Score 1) 84

by ahadsell (#62581448) Attached to: 'There is No Such Thing as Data'

the metric we're using is very broken

How so? It seems to me that it measures "engagement", which is exactly what you want if you're Slashdot. You don't come here for answers, you come here for discussion. If you're intelligent, you may be able to separate some wheat from the chaff.

Submission + - Study That Argued EVs Aren't Cleaner Gets An Update (arstechnica.com)

Submitted by Anonymous Coward
An anonymous reader writes: Based on the data that it had to work with, the institute's study put the emissions at 150-200 kilograms of CO2 per kilowatt-hour of lithium-ion battery capacity—one of the highest estimates that has been published. But IVL recently took another pass at this effort, incorporating newer data and some slightly different methods. This new study puts the emissions at 61-106kg, depending on the energy sources and efficiencies of different manufacturing plants. That cuts the estimate in half and puts it much more in line with other studies. So what accounts for the change, exactly? A few things are going on here. The first is a simple methodological change—this study leaves out emissions associated with recycling the battery, which accounted for 15kg of CO2 in the 2017 estimate. There are different ways to define the boundaries of such a life-cycle analysis, including "cradle-to-grave" methods that cover disposal and "cradle-to-gate" methods that cover up to the point you receive the car. To make apples-to-apples comparisons, you have to know what kind of estimate you're looking at.

More importantly, the study took advantage of more recent data that measures emissions during critical steps in the manufacturing process. As the battery manufacturing industry matures, plants are running closer to capacity and with efficiency improvements. Battery chemistry, too, is shifting. [...] The cathodes and anodes of these batteries are made by mixing materials in a solvent (water or otherwise) and then evaporating the solvent to leave a powder behind. This drying dominates the energy use of the manufacturing process. More recent measurements of this process in operating plants are a major source of the difference between the new study and the 2017 study, which estimated 1.6 time to 3 times greater energy use for drying.

The new version also acknowledges that the electricity used in the manufacturing process is coming from cleaner sources and could potentially come entirely from renewables. That helps bring the low end of the estimated range down. Of the estimated 61-106kg of CO2 emissions per kilowatt-hour of battery capacity, 59kg comes from the raw materials used in the battery. Then, the manufacturing process accounts for 2-47kg, depending on the mix of energy sources used. The 2017 study used a slightly higher number for raw materials—60-70kg of CO2—but estimated manufacturing emissions at 70-110kg. Then, it added emissions associated with recycling.

Comment Re:Google (Score 2) 154

by ahadsell (#55588827) Attached to: Spam Is Back

You are correct, in that Google ignores periods in gmail account names. a.b.c@gmail.com, ab.c@gmail.com and abc@.gmail.com are all the same account.

Comment Re:Must? (Score 1) 235

by ahadsell (#55209503) Attached to: Why Must You Pay Sales People Commissions?

This is my experience, too. The salesperson is the consistent presence in the cycle, understands the customer's needs, and interprets them to the team that will wind up fulfilling the contract.

There is a huge difference in the job of the salesperson at Best Buy, selling consumer products by the millions, and an engineering company, selling one-off systems to other companies. In the latter case, the salesperson earns his commission. In the former case maybe not so much.

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