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Biofuel’s Water Problem

Irrigating biofuel crops on a grand scale would be disastrous

2 min read
Photo: Jeremy Nixon/Alamy
Photo: Jeremy Nixon/Alamy

The great advantage of biofuel over petroleum is that the sources of biofuel are so widely available. The geologic fates may not have endowed your corner of the world with oil or gas deposits, but just about everyone can grow plants to make fuel. Unfortunately, some of the places these crops are grown require irrigation, and when water enters the equation, biofuels are a lot less attractive than the stuff they’re replacing.

Take soybeans. According to Carey W. King and Michael E. Webber of the University of Texas at Austin, the processing required to turn soybeans into biodiesel requires negligible water. But if you can’t depend on rain, raising the crop in the first place takes buckets. On average in the United States, 28 liters of irrigation water are needed to produce enough soybeans to propel an average vehicle 1 kilometer (12 gallons of water consumed per mile driven). Ethanol produced from corn grown on irrigated fields is almost as bad. Driving a typical flexible-fuel vehicle on E85 (85 percent ethanol fuel) produced from irrigated cornfields consumes about 26 L/km on average, assuming both the corn’s seed and stalks are transformed into ethanol.

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Video Friday: Humanoid Soccer

Your weekly selection of awesome robot videos

4 min read
Humans and human-size humanoid robots stand together on an indoor soccer field at the beginning of a game

Video Friday is your weekly selection of awesome robotics videos, collected by your friends at IEEE Spectrum robotics. We also post a weekly calendar of upcoming robotics events for the next few months. Please send us your events for inclusion.

CoRL 2022: 14–18 December 2022, AUCKLAND, NEW ZEALAND
ICRA 2023: 29 May–2 June 2023, LONDON

Enjoy today’s videos!

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Array of devices on a chip

This analog electrochemical memory (ECRAM) array provides a prototype for artificial synapses in AI training.

IBM research

How far away could an artificial brain be? Perhaps a very long way off still, but a working analogue to the essential element of the brain’s networks, the synapse, appears closer at hand now.

That’s because a device that draws inspiration from batteries now appears surprisingly well suited to run artificial neural networks. Called electrochemical RAM (ECRAM), it is giving traditional transistor-based AI an unexpected run for its money—and is quickly moving toward the head of the pack in the race to develop the perfect artificial synapse. Researchers recently reported a string of advances at this week’s IEEE International Electron Device Meeting (IEDM 2022) and elsewhere, including ECRAM devices that use less energy, hold memory longer, and take up less space.

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Designing Fuel Cell Systems Using System-Level Design

Modeling and simulation in Simulink and Simscape

1 min read
Designing Fuel Cell Systems Using System-Level Design

Design and simulate a fuel cell system for electric mobility. See by example how Simulink® and Simscape™ support multidomain physical modeling and simulation of fuel cell systems including thermal, gas, and liquid systems. Learn how to select levels of modeling fidelities to meet your needs at different development stages.