Sprawl is made possible by highways. This is expensive—in 2015, the Victoria Transport Policy Institute estimated that sprawl costs America more than $1 trillion a year in reduced business activity, environmental damage, consumer expenses, and other costs. Leaving aside the emissions from the 1.1 billion trips Americans take per day (87 percent of which are taken in personal vehicles), spreading everything out has eaten up an enormous amount of natural land.
— Read on slate.com/business/2019/02/green-new-deal-alexandria-ocasio-cortez-flaw-land-use.html
The challenges for space-based solar include the enormous cost of launching solar panels four square kilometers worth! into space and assembling them; avoiding damage from space debris and meteors; and keeping the power transmission beam locked on its ground-based receiver. That last issue is a security issue as well as an engineering challenge: the proposed satellite would beam energy to Earth using microwaves, and a 1 gigawatt beam, if concentrated, is enough vaporize 500 kilograms of water in a second. That’s the same as vaporizing 5 – 6 adults. The beam will not be that concentrated, but there are still obvious dangers from missing the target. Continue reading