Tuesday, July 31, 2018

Uber-uber post

A few of my posts over the past few months have had to do with Uber & Lyft, and I thought I'd keep all of this information in one place before adding an update.

Posts from March and April talks about how ridesharing has increased the numbers of miles driven and the numbers of trips taken in New York and Washington. The reason for this is that the services are subsidizing driving: more miles get driven when the cost of paying for vehicle use is lower.

The update, from the Washington Post's Faiz Siddiqui in July, shows that the numbers are staggering: 5.7 billion miles added in nine major urban areas. If public transit is working efficiently, vehicle miles spent in transit will be reduced, but use of transit goes up by about 2.6 miles per mile avoided. Commentators argue that households are buying fewer cars, but if the overall impact is to put cars on the road, that's a problem. A recent study finds that even automonous cars will increase traffic, since it may be cheaper to drive than to park! There may be a lot of traffic in our future.

Clearly ride-sharing is providing a convenient service, and it doesn't take too many months of renovations in the Metro system to be glad that we have ride-sharing systems. The important thing is to be aware of the full costs of the system, including time in traffic and taxes being paid by Uber and Lyft. As always, we economists are most interested in getting the best system for the costs!

Energy from a battery

While battery technology has improved by leaps and bounds over the past decade or two, this article about a giant battery sort of inside the earth is interesting to think about. The idea is simple: when there's extra flow coming out of a dam, the flow can be literally recycled back up above the turbines, saving the flow for when more charge is needed. There are some reservations about reusing the flow this way, particularly for those benefiting from downstream flow into nearby lakes, but the environmental savings are significant.

Saturday, July 21, 2018

Energy and land: bang for your buck

The last few posts have been about meat: how to get the most product at the lowest cost, where "cost" includes damage to the environment as well as producer costs. This article asks the same question: how to get the most product with the lowest costs, but this time the focus is on land. When we take a rock out of the ground and use that to drive our cars or even power our phones, that's a neat trick: hopefully it results in a small footprint environmentally while packing a wallop energy-wise. Of course, we need to be aware of the full set of costs of climate change, but one such cost is land.

This article by Joseph Kiesecker in the Nature Conservancy magazine is about the footprint of energy sources such as wind and solar. The land use costs are pretty high at the moment, though we can limit the damage by repurposing land on sites such as mines and waste pits. Still, keeping the same ideas in mind- getting the most energy at the lowest cost, while thinking of as many costs as possible- is a tried and true recipe for identifying different sides of important and difficult problems. There's always plenty to think about!

Ooo, post script: here is another example of the rising footprint of renewable energy sources. This article by Sarah Gilman for the Atlantic is about an endangered sea bird from northern Chile, where researchers have managed to track it a fascinating habitat underground.