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Comments by Geoffrey Styles Subscribe

On Energy Storage and the Cost of Going Off-Grid

Bob,

You're right about my assumption that off-grid = solar + storage. Not only was that the focus of the analysis on which I was reporting, but it is the combination I most often see in reference to going off-grid. It's also perceived as being universally available in the sense that the sun shines everwhere, aside from major differences in annual insolation, while not every home is connected to the gas "grid".

Your gas-generation option has other advantages, besides price. Because interruptions in gas supply are much rarer than power outages, let alone the cycles of PV cells, storage would only be necessary if peak instantaneous load were greater than the maximum output of the generator. That would allow storage to be sized differently: not just smaller but perhaps with a different chemistry or even based on ultracapacitors that excel at high discharge rates.

I also agree that choice entails trade-offs. Even the natural gas fuel cells marketed by high-profile companies with sterling green images may emit more CO2 per kWh than today's most efficient combined-cycle plants.

 

July 13, 2015    View Comment    

On Energy Storage and the Cost of Going Off-Grid

Thanks for that. Looks like a 9kW system (not small) in Mass. averaged 800 kWh/mo. last year.

July 9, 2015    View Comment    

On Energy Storage and the Cost of Going Off-Grid

The average US residential roof area is apparently around 1,500 ft2. For at least several months of the year the most populous parts of the US receive less than 3 kWh/m2/day of sunlight, suggesting that at 20% efficiency a fully covered solar roof in the Northeast, Midwest and Northwest would generate no more than 2,400 kWh in November, December, and January. That sounds like a lot until you factor in keeping a couple of EVs charged up, which seems likely to be equally appealing to those attracted to the off-grid lifestyle. That would consume around 600 kWh/month, leaving an amount roughly twice today's average household electricity usage. Of course storage capacity would have to be proportional to the size of the PV installation, to capture all the energy not used when generated.

It's not impossible, but it strikes me as wasteful, at least economically, considering the low cost (to the individual and society) of using the grid as your backup.

July 8, 2015    View Comment    

On Rare Earths Not So Rare?

Greg,

You raise some excellent points. Some reassurance comes from a item in the CFR study that I didn't highlight: recycling. As rare earth efficiency in new hardware grows, so does the opportunity to harvest rare earths tied up in outdated equipment. Wind farm repowering is a prime example. It's also worth noting that the supply of some metals that are scarce in stellar production terms isn't determined by the abundance of their single element ores, but rather by the processing of more abundant metals like copper with which they are often found as "tagalongs." Tellurium apparently falls into this category.

July 3, 2015    View Comment    

On Rare Earths Not So Rare?

Lewis,

Thanks very much for that explanation. If we targeted China on rare earth mining and processing pollution impacts, wouldn't we also want to look a bit harder at the PV lifecycle? Would I be cynical to think that these issues will get a pass in the interest of prioritizing CO2 emissions?

 

July 3, 2015    View Comment    

On Rare Earths Not So Rare?

As I pointed out below, if the intent was to bury this technology and these resources, why spin Molycorp off into a standalone company that was able to go public and get the financing to revamp its mine? Oil companies by the nature of the business they are in have large portfolios of unused land and dormant businesses. It would have been far easier, if what you are implying is right, to have quietly added Molycorp to such a list, where it would have soon been forgotten. I don't see any parallel to the Standard Oil/GM/Firestone case of 1949.

July 2, 2015    View Comment    

On Rare Earths Not So Rare?

Roger,

I guess I'd turn that last item around: If we're going to stand up for (more) democratic countries in what Russia considers its "near abroad", then we need to ensure we are not dependent on Russia for crucial supplies and services, including ISS crew transport and the rocket engines used in most of our heavy-lift capability, including military payloads. 

July 1, 2015    View Comment    

On Rare Earths Not So Rare?

Bob,

Perhaps my threshhold for conspiracies is a bit higher than yours, but in any case I think you have made a couple of assumptions here that need revisiting. The biggest is that Molycorp is ceasing operations, leaving Lynas alone to battle Chinese producers. That might still happen, but it's clear from their announcement that the Chapter 11 (reorganization) filing was intended to restructure their debt. From their press release: "the Company expects to exit Chapter 11 with an appropriate financing framework to support our business going forward".

You also suggested that oil companies might want to suppress rare earth mining. According to the company history, from 1977-2008 Molycorp was owned by Unocal and its successor Chevron (which merged with my former employer Texaco in 2001). In 2008 Chevron spun off Molycorp in a transaction that apparently took it private. Seems like either company could have simply shut it down and left it at that. In fact, rare earths are used in oil refining catalysts, which might provide an explanation for why Unocal acquired the operation in the 1970s.

June 30, 2015    View Comment    

On Rare Earths Not So Rare?

Joris,

Perhaps someone more familiar with the relevant WTO provisions can chime in here, but I would think that the kind of tariff you are suggesting would immediately run afoul of these rules.

June 30, 2015    View Comment    

On Where Is the Stimulus from Cheap Oil?

Bruce,

That's correct, as far as it goes. However, US energy use per real dollar of GDP in 1973 was more than double what it is today, and oil accounted for 46% of US energy consumption, compared to 35% last year. All of that adds up to less impact now from an oil price spike at any given level of imports.

June 10, 2015    View Comment    

On EPA's Blown Call on Ethanol

Rick,

Whenever you disagree with me, I've probably missed something. We've discussed the conversion from corn to distillers grains before, and I get the protein uplift. My concern is with the collision between rising quantities of ethanol and fleets and fueling infrastructure that weren't built to handle them. If folks want to pay more (per BTU) to burn E85 in cars equipped to handle it, that's a valid choice in a consumer economy.

However, I wonder if you've done a thorough literature search on the claim that ethanol "cleans up the air".  What do you make of studies showing ethanol blends yield higher emissions of aldehydes and ketones? Nature reported on the increase in ground level ozone connected to the use of large quantities of neat ethanol and high-ethanol blends in Brazil. This effect was previously highlighted in Scientific American.

June 6, 2015    View Comment    

On EPA's Blown Call on Ethanol

Well said. Of course quality over quantity can still result in GDP growth, which hasn't just been about producing more widgets in decades.

June 5, 2015    View Comment