Solar thermal

Who hasn't enjoyed heat from the sun? Doing so represents a direct energetic transfer—via radiation—from the sun's hot surface to your skin...We have already seen that solar PV qualifies as a super-abundant resource, requiring panels covering only about 0.5% of land to meet our entire energy demand (still huge, granted). So direct thermal energy from the sun, gathered more efficiently than what PV can do, is automatically in the abundant club. Let's evaluate some of the practical issues surrounding solar thermal: either for home heating or for the production of electricity.

- The end of the U.S. ethanol tariff
- Building a better suntrap
- Storehouses for Solar Energy Can Step In When the Sun Goes Down

How fast do we need to transition off of fossil fuels? What industrial capacity is available today for different alternative energy technologies and what is likely to be available in the future? What might we do if we can't replace fossil fuels with alternatives fast enough, and what might the consequences be? I finally got around to re-doing these calculations, and wanted to go through the numbers.

Most discussions of the future of electric power start from the assumption that maintaining a grid of the modern kind, designed from top to bottom around ample supplies of cheap fossil fuels, is the only option there is. It's long past time to revisit that notion. Are our current ways of electricity production, distribution, and use merely the extravagant habits of a temporary age of excess, and what might an appropriate system for producing and using electricity look like in an age of scarcity?

The Energy Report aligns with several others in recent years in confidently claiming that we could transition to full reliance on renewable energy, without any disruption of high material living standards or the pursuit of economic growth. These reports are typically quite impressive involving glossy formats with lots of coloured graphs and pictures, a large cast of heavy-weight authors, and a long list of high-powered endorsements.

Confusion around the true extent of the spare oil production capacity of Saudi Arabia increased this week following a statement by Saudi oil minister Ali al-Naimi that his country had reduced production in March by 800,000 barrels--this despite the loss of 1 million barrels/day of production from Libya. Al Naimi went on to claim that global markets are currently oversupplied.

Whether or not renewables can save consumer-capitalist society depends heavily on solar thermal electricity, because unlike wind and photovoltaic energy it can be coupled with large scale storage and so can deal much more effectively with the problem of the intermittency of wind and sun. But can it enable total dependence on renewables?

Obama's recent speech on energy policy, which rehashed nearly every cliché uttered in forty years of empty White House rhetoric on the subject, drove home the hard fact that meaningful responses to the predicament of industrial society will not be forthcoming from the American political class. Instead, the foundations of a very different kind of energy system - localized, small-scale, and based on diffuse renewable energy - will need to be laid by individuals, families, and community groups. Passive solar technologies offer one useful example of how the ecotechnic energy system of the future can begin to evolve.

In the wake of the Japanese nuclear debacle, we need a practical and affordable clean electricity plan that does not rely on new nuclear power. This article presents just such a Plan. New nuclear is absent from the Plan not because of any safety concern, but simply because it fails the "practical and affordable" test. President Obama called for "80% Clean Energy" by 2035. This Plan presents how we can do it right.

The backyard organic gardens central to the current series of posts on The Archdruid Report -- and equally central to most strategies for relocation in the face of looming energy shortages -- have a lot of work to do in the period between the last frosts of spring and the first frosts of fall. Stretching that interval, by way of "time machines" drawn from appropriate technology, can help make growing part of one's own food a more viable proposition.

Luke Skywalker had to master the ways of the Force to save the galaxy. We face a similar challenge -- mastering the ways of energy, which are surprisingly counterintuitive to people raised in current ways of thinking -- in order to make use of the limited options still open to us in an age of declining energy supplies.

People in the Dark Ages filled in the gaps in the very limited knowledge base available to them with the help of wizards and soothsayers. As we close in on a future for which most people are hopelessly unprepared, a new kind of wizard -- a green wizard, adept in the forgotten arts of appropriate tech -- may be one of the things that a deindustrializing world needs most.

Too many discussions of the future after peak oil start from the assumption that the only alternative to collapse is maintaining the arrangements for energy distribution and use we have today. This kind of thinking, rooted in a logic of abundance shaped by three extraordinary centuries of unparalleled energy glut, forms one of the principal barriers in the way of workable responses to a challenging future.

The difference between diffuse and concentrated energy sources, the theme of last week's Archdruid Report post, means that some of today's highly touted alternative energy schemes may be worth much less than currently claimed, while other technologies that receive much less attention may be the wave of the future. A closer consideration of energy concentration and its effects helps clarify which is which.

Solar thermal is a way of harnessing the largest source of energy available to us, so in this post I'll have a look at the upswing in interest in the use of this technology for electricity generation in recent years and look at some of the approaches being pursued to make it economically competitive with coal fired power generation.