Renewables: The Next Fracking?

“Broadly speaking, there are two groups of people who talk about renewable energy these days. The first group consists of those people who believe that of course sun and wind can replace fossil fuels and enable modern industrial society to keep on going into the far future. The second group consists of people who actually live with renewable energy on a daily basis. It’s been my repeated experience for years now that people belong to one of these groups or the other, but not to both.”

renewables“As a general rule, in fact, the less direct experience a given person has living with solar and wind power, the more likely that person is to buy into the sort of green cornucopianism that insists that sun, wind, and other renewable resources can provide everyone on the planet with a middle class American lifestyle.”

“Conversely, those people who have the most direct knowledge of the strengths and limitations of renewable energy—those, for example, who live in homes powered by sunlight and wind, without a fossil fuel-powered grid to cover up the intermittency problems—generally have no time for the claims of green cornucopianism, and are the first to point out that relying on renewable energy means giving up a great many extravagant habits that most people in today’s industrial societies consider normal.”

Read more at The Archdruid Report: Renewables: The Next Fracking?

A World Made of Rotor Blades

public seating rotor blades close

Almost a quarter of a million windmills worldwide will need to be replaced by 2030. The rotor blades are made of valuable composite materials that are difficult to recover at the end of their energy generating life. New generation rotor blades made of glass or carbon fibre composite material have average lifespans of between 10 and 25 years. Recycling of glass fibre composite is possible though complex. Recycling of the more highly valued carbon fibre composite is currently impossible. In many EU countries landfill of carbon composites is now prohibited. Thus, many rotor blades at the end of their wind turbine life are currently shredded and incinerated. At current growth rates, by 2034, there will be about 225,000 tonnes of rotor blade composite material produced annually, worldwide.

The Dutch firm Superuse Studios has found a solution to the growing mountains of waste generated by the wind industry: making use of end-of-life rotor blades in design and architecture. The realised projects demonstrate the technical applications and potential for blade made designs and architecture. In their second life as design and architectural elements, rotor blades could be used for a further 50-100 years, or more. Blade made designs are durable, iconic, compete economically, and reduce the ecological footprint of projects in which they are used. [Read more…]

The Energetic Implications of Energy Storage

“When renewable energy sources such as solar and wind farms generate more electricity than consumers need, storing the excess doesn’t always make sense. Large, grid-scale batteries capable of storing the extra electricity are resource-intensive and costly to manufacture and maintain — sometimes more so than the energy they’re used to store.”

The energetic implications of curtailing versus storing solar- and wind-generated electricity, Charles J. Barnhart et al, Energy & Environmental Science, Issue 10, 2013. Open access. Via Eurekalert and Yale Environment 360.

Energy Cannibalism

Energy cannibalism refers to an effect where rapid growth of an entire energy producing (or conserving) technology industry creates a need for energy that uses (or cannibalizes) the energy of existing power plants or devices. For the deployment of renewable energy and energy efficiency technologies to grow while remaining net greenhouse gas emission mitigators, they must grow at a rate slower than the inverse of their energy payback time.

Previously: Can renewables power consumer societies? The negative case.

Jet Stream Wind Power as a Renewable Energy Resource

“Jet streams are regions of sustained high wind speeds in the upper atmosphere and are seen by some as a substantial renewable energy resource. However, jet stream motion is associated with very small generation rates of kinetic energy to maintain the high wind velocities, and it is this generation rate that will ultimately limit the potential use of jet streams as a renewable energy resource. We have calculated that the maximum sustainable extraction from jet streams of the global atmosphere is about 7.5 TW. This estimate is about 200-times less than previous estimates and is due to the fact that the common expression for instantaneous wind power merely characterizes the transport of kinetic energy by the flow, but not the generation rate of kinetic energy.”

Climate change

“We also find that when maximum wind power is extracted from the jet streams, it results in significant climatic impacts due to a substantial increase of heat transport across the jet streams in the upper atmosphere. This results in upper atmospheric temperature differences of >20 °C, greater atmospheric stability, substantial reduction in synoptic activity, and substantial differences in surface climate. We conclude that jet stream wind power does not have the potential to become a significant source of renewable energy.”

Jet stream wind power as a renewable energy resource: little power, big impacts. Earth System Dynamics, November 2011.

Can Renewables Power Consumer Societies? The Negative Case

“Virtually all current discussion of climate change and energy problems proceeds on the assumption that technical solutions are possible within basically affluent-consumer societies. There is however a substantial case that this assumption is mistaken. This case derives from a consideration of the scale of the tasks and of the limits of non-carbon energy sources, focusing especially on the need for redundant capacity in winter. The first line of argument is to do with the extremely high capital cost of the supply system that would be required, and the second is to do with the problems set by the intermittency of renewable sources. It is concluded that the general climate change and energy problem cannot be solved without large scale reductions in rates of economic production and consumption, and therefore without transition to fundamentally different social structures and systems.”

Read more: “Can renewables solve the greenhouse problem? The negative case” (pdf), Ted Trainer, Energy Policy, March 2010. Also check out the author’s website, where you can find similar papers, like this one.