Posted by Max Dunn Fri, 18 Sep 2009 02:27:41 GMT | no comments
Here is a study that looked at Energy Return on Invested (EROI) of windmills and found they returned over 20 times the energy use to make them, which is favorable with fossil fuels, nuclear and solar power.
Meta-analysis of net energy return for wind power systems
Posted by Max Dunn Wed, 16 Sep 2009 23:22:53 GMT | no comments
Many business are built entirely around extrinsic motivators – carrots and sticks. That’s actually fine for many kinds of 20th century mechanistic tasks. But for 21st century cognitive tasks, monetary rewards just don’t work.
This has been confirmed over and over again. Dan Ariely found that when tasks called for even rudimentary cognitive skill, a larger reward led to poorer performance. The London School of Economics reports: “We find that financial incentives can result in a negative impact on overall performance.”
What does work? Autonomy, mastery and purpose. Find out more in this fascinating and important talk by Dan Pink on TED.
Posted by Max Dunn Thu, 10 Sep 2009 21:34:37 GMT | 1 comment
Some people claim that more energy goes into making a solar photovoltaic (PV) panel than it will ever produce. While years ago that may have been the case, it certainly isn’t true any longer.
The US Department of Energy looked at several studies and concluded that multi-crystalline PV has an energy payback of less than 4 years and this will likely go down to below 2 years soon. Thin-film technologies have an even shorter payback period. With an estimated 30-year life, solar PV is actually a very good energy investment!
Posted by Max Dunn Mon, 07 Sep 2009 18:07:11 GMT | no comments
John Mackey, the founder and CEO of Whole Foods, has a great definition of what a business should be:
“Business has noble purposes: to provide goods and services that improve its customers’ lives, to provide jobs and meaningful work for employees, to create wealth and prosperity for its investors, and to be a responsible and caring citizen.”
Posted by Max Dunn Mon, 03 Aug 2009 16:57:33 GMT | no comments
What would you think is the safer car to drive – the Toyota Camry at 3300 pounds or the Ford Explorer at 4800 pounds. Would you believe the lighter Camry?
Safety statistics show this to be true. For every million Camrys on the road, 41 Camry drivers perish in crashes and an additional 29 people die in accidents involving Camrys. However, for every million Ford Explorers on the road, 88 Explorer drivers die and it kills 60 other people. So driving an Explorer is twice as dangerous as driving a Camry!
Why is this? The bigger Explorer can’t avoid accidents as easily as the nimbler Camry and is more prone to rollovers.
So next time someone says they feel safer in a big car, point out that the smaller car is actually safer.
References:Posted by Max Dunn Tue, 28 Jul 2009 14:32:11 GMT | no comments
When looking at the economics of building solar panels, one important factor is how much the factory costs.
By comparison, the fuel for a nuclear power plant is very inexpensive and the main reason why nuclear power is so expensive is that the nuclear plants cost so much to build. Is this also true for solar panels? Do solar panel factories costs so much that even if the marginal cost of producing a solar panel comes down, will the cost of the factory still keep the prices high?
If the recent announcement of a thin-film solar panel factory is any indication, then solar panel plant costs are very low.
This factory will cost about $150 million dollars and produce 100 MW of solar panels per year. Over 10 years, this will add only $0.15 per watt to the cost of the panel. Considering that we only need to get solar power down to about $2.00 per watt to be competitive to coal, the cost of the factory is not a problem.
So it appears that the cost of solar panel factories will not be the limiting factor in bringing down the cost of solar power.
Posted by Max Dunn Sat, 25 Jul 2009 15:08:16 GMT | no comments
A friend of mine recently got a 400cc Suzuki Burgman scooter and loves it. He gets 53 MPG which is pretty good, but realized that it was about the same as a Prius that gets 48 MPG. “Why is this?”, he asked. The Prius weighs about 3000 lbs while the scooter is only 400 lbs.
Let’s look into this.
Regenerative Breaking
Even though the scooter is a lot lighter, the Prius captures about 50% of the energy when breaking and uses it to accelerate. So this brings the effective weight of the Prius down to 1500 lbs.
Wind Resistance
Even though the scooter has a frontal area 4 times smaller than a Prius, a scooter is not very smooth going through the air. It has a coefficient of drag (Cd) of about 0.9 versus about 0.26 for the Prius. Adding this up, the total drag coefficient (Cd x A) for the Prius is 6.24 and the scooter is 5.4. This means that the scooter takes almost as much energy to overcome wind resistance as the Prius!
Motor Efficiency
Small engines are not very efficient, while Prius engines are very efficient.
Conclusion
Add them up: the extra weight is not as significant because of regenerative breaking, the wind resistance is about the same and the motor is much less efficient. Given all this, it is not surprising that the scooter and the Prius get about the same gas mileage!
Posted by Max Dunn Mon, 29 Jun 2009 16:17:01 GMT | 1 comment
One of the factors that we often forget when comparing Electric Vehicles (EVs) to gas powered cars is that it takes a lot of energy to extract and refine oil into gas.
For instance, in California it takes about 14kWh of electricity to get a barrel of oil out of the ground, and about double that to refine it. About half a barrel of oil gets refined into gas, which means this 20 gallons of gas takes about 21 kWh of electricity.
It also takes a lot of natural gas to refine oil, and if this natural gas was used instead to produce electricity, it would produce about another 20 kWh of electricity.
Therefore in a typical gas car that 20 gallons will last 400 miles. But if we just left that barrel of oil in the ground and used the electricity and natural gas for an EV instead, we could go about 120 miles or about 30% of the distance of the ICE car.
So the next time a comparison is made between the efficiency of gas cars and EVs, remember even before the gas gets into the tank, we are already giving up 30% of the energy that we could have used to power an electric vehicle.
Posted by Max Dunn Tue, 12 May 2009 16:13:05 GMT | no comments
- Michael Reilly, Discovery News, May 11, 2009 – Forget peak oil, a series of new estimates of the world’s coal supply suggests reserves may be vastly overestimated, and if the planet isn’t running on a majority of alternative energies within the next few decades, we could be facing an unprecedented global energy crisis.
On the flip side, a dwindling supply of coal could also throw the breaks on global warming, some argue.
Common knowledge about coal is that major producing nations like China, the United States and Australia, have enough to last hundreds of years, far beyond the reach of oil, which may already be in its twilight years. But worldwide coal production could plateau as early as 2025, according to one new estimate, and a growing group of scientists are concerned that fossil fuel supplies may begin dwindling by mid-century.
Last year, David Rutledge of the California Institute of Technology analyzed the coal production patterns of five regions around the world – eastern Pennsylvania, France, Germany’s Ruhr Valley, the United Kingdom and Japan – each of which was producing at less than a tenth of its peak levels.
He found that each of the depleted regions followed a rough bell curve of production; initial production was followed by a steep ramp-up, a plateau near peak levels, and then a consistent decline.
When he applied the same formula to coal data from around the world, the results were startling: the United Nations Intergovernmental Panel on Climate Change’s maximum estimate for extractable coal is about 3,400 billion tons. Rutledge’s calculations suggest just 666 billion tons.
Posted by Max Dunn Tue, 12 May 2009 15:55:33 GMT | no comments
by Steven Kopits, Managing Director, Douglas-Westwood, New York, 5/11/2009
NEW YORK: In seeking to explain the run up in oil prices from 2004 to 2008, commentators often turn to “speculation” as the primary cause. While speculation – or at least a kind of piling-on – may have explained the very late stages of the oil price rally, the willingness to attribute oil prices primarily to financial investors – as the CBS news show ‘60 Minutes’ did a few months back – risks drawing the wrong lesson from the period. Let’s re-wind the clock and recall the events of the time.