Category Archives: Energy

the posts in this category used to be in “Energy in A Nutshell” at my former web site.

All About Coal

[Below are my notes, statistics, and so on about coal from many publications] United States Coal Production     Coal Production Map by region (2011 million short tons, % change from 2010). Source: Quarterly Coal Report, October- December 2011 (April … Continue reading

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Hydropower has a very low energy density

To store the energy contained in 1 gallon of gasoline requires over 55,000 gallons to be pumped up 726 feet (CCST 2012). As a thought experiment look at what it would take generate all of America’s 4,058 TWh electricity, where … Continue reading

Posted in Energy Storage, Hydropower | 1 Comment

EROI negative for Coal-to-Liquids (CTL) at Shenuha Direct Coal Liquefaction plant

Kong, Z. et al. 23 January 2015. EROI Analysis for Direct Coal Liquefaction without and with CCS: The Case of the Shenhua DCL Project in China. Energies 8(2): 786-807.   Many nations see coal-to-liquids (CTL) as a way to avoid … Continue reading

Posted in Coal to Liquids (CTL), EROEI Energy Returned on Energy Invested | Leave a comment

CSP Barriers and Obstacles

Location must be in the desert Southwest Unlike solar PV, CSP can’t cope with humidity or cloud cover, so it is limited to the southwest were the solar irradiation is high and there is no dust, haze, or smog.  Solar … Continue reading

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CSP with thermal energy storage is seasonal, so it can not balance variable power or contribute much power for half the year

Concentrated Solar Power not only needs lots of sunshine, but no humidity, clouds, dust, smog or or anything else that can scatter the sun’s rays.  Above 35 degrees latitude north or south, the sun’s rays have to pass through too … Continue reading

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Concentrated Solar Power: Water Constraints

CRS. 2009. Water Issues of Concentrating Solar Power (CSP) Electricity in the U.S. Southwest. Congressional Research Service. As you can see in the two maps below, the best sites for CSP are also the most water challenged.       … Continue reading

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Concentrated Solar Power: location, location, location

Location, Location, Location:   What follows is from: SBC. June 2013. Concentrating Solar Power. SBC Energy Institute. The best sites are between 10° and 40°, South or North. As you can see in the chart below, this makes a huge difference, … Continue reading

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Short-circuiting a solar boom in Japan

Spain is still feeling the painful effects of the costs of overbuilt solar PV, and now Japan is finding itself in the same position.  This article does a lousy job of explaining that the grid must be in exact supply … Continue reading

Posted in Distributed Generation, Grid instability, Photovoltaic Solar, Renewable Integration | Leave a comment

Wind turbines hit limits to growth before 50% wind power penetration

Material requirements of 50% wind power in the USA hit limits to growth Also see Davidsson, S., et al. 2014. Growth curves and sustained commissioning modelling of renewable energy Investigating resource constraints for wind energy. Energy Policy. Wind turbines can’t … Continue reading

Posted in Alternative Energy Resources, Electrification, Limits To Growth, Renewable Integration, Wind | Tagged , , , , , , , , , , , | 2 Comments

Wind’s dirty secret: it goes on vacation in the summer

  Figure 1. Summer wind across the USA is nearly all sluggish Class 3 (light blue), Class 2 (orange) or class 1 (blank) (NREL). Someday wind and solar will need to contribute over 50% of power due to declining fossil … Continue reading

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