The Latest Smart Grid/Smart Energy News From Around the World

The Go-To Site for Actionable Smart Energy News

Vol.3, No.16: April 21, 2014

 Publisher's Note

All of us at Smart Energy Universe are most excited with the updated look of our web site. As an added bonus it offers ease of viewing on mobile devices , our readers can “read all about the smart energy world ” anytime, anyplace.

This week is Earth Day and we may have found Earth 2:


The artist's concept depicts Kepler-186f , the first validated Earth-size planet to orbit a distant star in the habitable zone. Image: NASA Ames/SETI Institute/JPL-Caltech





The diagram compares the planets of our inner solar system to Kepler-186, a five-planet star system about 500 light-years from Earth in the constellation Cygnus. The five planets of Kepler-186 orbit an M dwarf, a star that is half the size and mass of the sun. Image: NASA Ames/SETI Institute/JPL-Caltech


 "The discovery of Kepler-186f is a significant step toward finding worlds like our planet Earth," said Paul Hertz, NASA's Astrophysics Division director at the agency's headquarters. Kepler-186f resides in the Kepler-186 system, about 500 light-years from Earth in the constellation Cygnus. The system is also home to four companion planets, which orbit a star half the size and mass of our sun.Kepler-186f orbits its star once every 130-days and receives one-third the energy from its star that Earth gets from the sun, placing it nearer the outer edge of the habitable zone. On the surface of Kepler-186f, the brightness of its star at high noon is only as bright as our sun appears to us about an hour before sunset.

Click here to read the rest of the article.

The U.S. Environmental Protection Agency (EPA) released its 19th annual report of overall U.S. greenhouse gas (GHG) emissions, showing a 3.4 percent decrease in 2012 from 2011. The Inventory of U.S. Greenhouse Gas Emissions and Sinks, which is submitted annually to the Secretariat of the United Nations Framework Convention on Climate Change, presents a national-level overview of annual greenhouse gas emissions since 1990.

The major contributors to the decrease in emissions from 2011-2012 were the decrease in energy consumption across all sectors in the U.S. economy, and the decrease in carbon intensity for electricity generation due to fuel switching from coal to natural gas. Other factors included a decrease in transportation sector emissions attributed to an increase in fuel efficiency across different transportation modes and limited new demand for passenger transportation.

Greenhouse gases are the primary driver of climate change, leading to increased heat-related illnesses and deaths; worsening the air pollution that can cause asthma attacks and other respiratory problems; and expanding the ranges of disease-spreading insects. Climate change is also affecting the frequency and intensity of heat waves, droughts, and other extreme weather events.

Under the Climate Action Plan, EPA is taking steps to address carbon pollution from the power and transportation sectors, and to improve energy efficiency in homes, businesses and factories. This includes increasing fuel efficiency for cars and light trucks for model years 2012-2025 that, over the lifetime of these vehicles, will save Americans more than $1.7 trillion. In addition, we are increasing energy efficiency through the Energy Star program that saved Americans more than $26 billion in utility bills in 2012.

According to the report, GHG emissions in 2012 showed a 10 percent drop below 2005 levels. Total emissions of the six main greenhouse gases in 2012 were equivalent to 6,526 million metric tons of carbon dioxide. These gases include carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons and sulfur hexafluoride.


EPA develops an annual report called the Inventory of U.S. Greenhouse Gas Emissions and Sinks (Inventory). This report tracks total annual U.S. emissions and removals by source, economic sector, and greenhouse gas going back to 1990. EPA uses national energy data, data on national agricultural activities, and other national statistics to provide a comprehensive accounting of total greenhouse gas emissions for all man-made sources in the United States. EPA also collects greenhouse gas emissions data from individual facilities and suppliers of certain fossil fuels and industrial gases through the Greenhouse Gas Reporting Program. The most recent Inventory report is available for download at the bottom of this page.

The national greenhouse gas inventory is submitted to the United Nations in accordance with the Framework Convention on Climate Change. In preparing the annual emissions inventory report, EPA collaborates with hundreds of experts representing more than a dozen U.S. government agencies, academic institutions, industry associations, consultants and environmental organizations.


Overview of Greenhouse Gases


Sources of Greenhouse Gas Emissions


Greenhouse Gas Emission Trend

Greenhouse Gas Emissions by Gas

As the largest source of U.S. greenhouse gas emissions, CO2 from fossil fuel combustion has accounted for approximately 78 percent of GWP-weighted emissions since 1990, and is approximately 78 percent of total GWP-weighted emissions in 2012. Emissions of CO2 from fossil fuel combustion increased at an average annual rate of 0.3 percent from 1990 to 2012. The fundamental factors influencing this trend include (1) a generally growing domestic economy over the last 23 years, (2) an overall growth in emissions from electricity generation and transportation activities, along with (3) a general decline in the carbon intensity of fuels combusted for energy in recent years by most sectors of the economy.

Between 1990 and 2012, CO2 emissions from fossil fuel combustion increased from 4,745.1 Tg CO2 Eq. to 5,072.3 Tg CO2 Eq.—a 6.9 percent total increase over the twenty-three-year period. From 2011 to 2012, these emissions decreased by 198.8 Tg CO2 Eq. (3.8 percent).

Transportation End-Use Sector

When electricity-related emissions are distributed to economic end-use sectors, transportation activities accounted for 34.4 percent of U.S. CO2 emissions from fossil fuel combustion in 2012. The largest sources of transportation greenhouse gases in 2012 were passenger cars (43.1 percent); light duty trucks, which include sport utility vehicles, pickup trucks, and minivans (18.4 percent), freight trucks (21.9 percent), commercial aircraft (6.2 percent), rail (2.5 percent), and ships and boats (2.2 percent). These figures include direct emissions from fossil fuel combustion used in transportation and emissions from non-energy use (i.e. lubricants) used in transportation, as well as HFC emissions from mobile air conditioners and refrigerated transport allocated to these vehicle types.

In terms of the overall trend, from 1990 to 2012, total transportation emissions rose by 18 percent due, in large part, to increased demand for travel with limited gains in fuel efficiency over the same time period. The number of vehicle miles traveled by light-duty motor vehicles (passenger cars and light-duty trucks) increased 35 percent from 1990 to 2012, as a result of a confluence of factors including population growth, economic growth, urban sprawl, and low fuel prices during the beginning of this period. Almost all of the energy consumed for transportation was supplied by petroleum-based products, with more than half being related to gasoline consumption in automobiles and other highway vehicles. Other fuel uses, especially diesel fuel for freight trucks and jet fuel for aircraft, accounted for the remainder. The primary driver of transportation-related emissions was CO2 from fossil fuel combustion, which increased by 16 percent from 1990 to 2012. This rise in CO2 emissions, combined with an increase in HFCs from close to zero emissions in 1990 to 72.9 Tg CO2 Eq. in 2012, led to an increase in overall emissions from transportation activities of 18 percent.

Industrial End-Use Sector

Industrial CO2 emissions, resulting both directly from the combustion of fossil fuels and indirectly from the generation of electricity that is consumed by industry, accounted for 27 percent of CO2 from fossil fuel combustion in 2012. Approximately 57 percent of these emissions resulted from direct fossil fuel combustion to produce steam and/or heat for industrial processes. The remaining emissions resulted from consuming electricity for motors, electric furnaces, ovens, lighting, and other applications. In contrast to the other end-use sectors, emissions from industry have steadily declined since 1990. This decline is due to structural changes in the U.S. economy (i.e., shifts from a manufacturing-based to a service-based economy), fuel switching, and efficiency improvements.

Residential and Commercial End-Use Sectors

The residential and commercial end-use sectors accounted for 20 and 18 percent, respectively, of CO2 emissions from fossil fuel combustion in 2012. Both sectors relied heavily on electricity for meeting energy demands, with 72 and 78 percent, respectively, of their emissions attributable to electricity consumption for lighting, heating, cooling, and operating appliances. The remaining emissions were due to the consumption of natural gas and petroleum for heating and cooking. Emissions from the residential and commercial end-use sectors have increased by 9 percent and 19 percent since 1990, respectively, due to increasing electricity consumption for lighting, heating, air conditioning, and operating appliances.

Electricity Generation

The United States relies on electricity to meet a significant portion of its energy demands. Electricity generators consumed 35 percent of total U.S. energy uses from fossil fuels and emitted 40 percent of the CO2 from fossil fuel combustion in 2012. The type of fuel combusted by electricity generators has a significant effect on their emissions. For example, some electricity is generated through non-fossil fuel options such as nuclear, hydroelectric, or geothermal energy. Including all electricity generation modes, generators relied on coal for approximately 39 percent their total energy requirements in 2012. In addition, the coal used by electricity generators accounted for 93 percent of all coal consumed for energy in the United States in 2012. Recently a decrease in the carbon intensity of fuels consumed to generate electricity has occurred due to a decrease in coal consumption, and increased natural gas consumption and other generation sources. Including all electricity generation modes, electricity generators used natural gas for approximately 29 percent of their total energy requirements in 2012. Across the time series, changes in electricity demand and the carbon intensity of fuels used for electricity generation have a significant impact on CO2 emissions.

Other significant CO2 trends included the following:

  • CO2 emissions from non-energy use of fossil fuels have decreased by 10.5 Tg CO2 Eq. (8.7 percent) from 1990 through 2012. Emissions from non-energy uses of fossil fuels were 110.3 Tg CO2 Eq. in 2012, which constituted 2.0 percent of total national CO2 emissions, approximately the same proportion as in 1990.
  • CO2 emissions from iron and steel production and metallurgical coke production decreased by 5.7 Tg CO2 Eq. (9.5 percent) from 2011 to 2012, reversing a two-year trend of increasing emissions primarily due to increased steel production associated with improved economic conditions. Despite this, from 1990 through 2012, emissions declined by 45.6 percent (45.5 Tg CO2 Eq.). This overall decline is due to the restructuring of the industry, technological improvements, and increased scrap utilization.
  • In 2012, CO2 emissions from cement production increased by 3.0 Tg CO2 Eq. (9.5 percent) from 2011. After decreasing in 1991 by 2.2 percent from 1990 levels, cement production emissions grew every year through 2006 except for a slight decrease in 1997. Since 2006, emissions have fluctuated through 2012 to the economic recession and associated decrease in demand for construction materials. Overall, from 1990 to 2012, emissions from cement production have increased by 5.3 percent, an increase of 1.8 Tg CO2 Eq.
  • Net CO2 uptake from Land Use, Land-Use Change, and Forestry increased by 148.2 Tg CO2 Eq. (17.8 percent) from 1990 through 2012. This increase was primarily due to an increase in the rate of net carbon accumulation in forest carbon stocks, particularly in aboveground and belowground tree biomass, and harvested wood pools. Annual carbon accumulation in landfilled yard trimmings and food scraps slowed over this period, while the rate of carbon accumulation in urban trees increased.

Methane Emissions

Methane (CH4) is more than 20 times as effective as CO2 at trapping heat in the atmosphere (IPCC 1996). Over the last two hundred and fifty years, the concentration of CH4 in the atmosphere increased by 151 percent (IPCC 2007). Anthropogenic sources of CH4 include natural gas and petroleum systems, agricultural activities, landfills, coal mining, wastewater treatment, stationary and mobile combustion, and certain industrial processes.

Some significant trends in U.S. emissions of CH4 include the following:

  • Enteric fermentation is the largest anthropogenic source of CH4 emissions in the United States. In 2012, enteric fermentation CH4 emissions were 141.0 Tg CO2 Eq. (24.9 percent of total CH4 emissions), which represents an increase of 3.1 Tg CO2 Eq. (2.3 percent) since 1990. This increase in emissions from 1990 to 2012 in enteric generally follows the increasing trends in cattle populations. From 1990 to 1995 emissions increased and then decreased from 1996 to 2001, mainly due to fluctuations in beef cattle populations and increased digestibility of feed for feedlot cattle. Emissions generally increased from 2005 to 2007, though with a slight decrease in 2004, as both dairy and beef populations underwent increases and the literature for dairy cow diets indicated a trend toward a decrease in feed digestibility for those years. Emissions decreased again from 2008 to 2012 as beef cattle populations again decreased.
  • Natural gas systems were the second largest anthropogenic source category of CH4 emissions in the United States in 2012 with129.9 Tg CO2 Eq. of CH4 emitted into the atmosphere. Those emissions have decreased by 26.6 Tg CO2 Eq. (17.0 percent) since 1990. The decrease in CH4 emissions is largely due to the decrease in emissions from production and distribution. The decrease in production emissions is due to increased voluntary reductions, from activities such as replacing high bleed pneumatic devices, and the increased use of plunger lifts for liquids unloading, and increased regulatory reductions. The decrease in distribution emissions is due to a decrease in cast iron and unprotected steel pipelines. Emissions from field production accounted for 32.2 percent of CH4 emissions from natural gas systems in 2012. CH4 emissions from field production decreased by 25.2 percent from 1990 through 2012; however, the trend was not stable over the time series-emissions from this source increased by 23.4 percent from 1990 through 2006 due primarily to increases in hydraulically fractured well completions and workovers, and then declined by 39.4 percent from 2006 to 2012. Reasons for the 2006-2012 trend include an increase in plunger lift use for liquids unloading, increased voluntary reductions over that time period (including those associated with pneumatic devices), and Reduced Emissions Completions (RECs) use for well completions and workovers with hydraulic fracturing.
  • Landfills are the third largest anthropogenic source of CH4 emissions in the United States (102.8 Tg CO2 Eq.), accounting for 18.1 percent of total CH4 emissions in 2012. From 1990 to 2012, CH4 emissions from landfills decreased by 44.9 Tg CO2 Eq. (30.4 percent), with small increases occurring in some interim years. This downward trend in overall emissions can be attributed to a 21 percent reduction in the amount of decomposable materials (i.e., paper and paperboard, food scraps, and yard trimmings) discarded in MSW landfills over the time series (EPA 2010) and an increase in the amount of landfill gas collected and combusted, which has more than offset the additional CH4 emissions resulting from an increase in the amount of municipal solid waste landfilled.
  • In 2012, CH4 emissions from coal mining were 55.8 Tg CO2 Eq., a 4.0 Tg CO2 Eq. (6.7 percent) decrease below 2011 emission levels. The overall decline of 25.2 Tg CO2 Eq. (31.1 percent) from 1990 results from the mining of less gassy coal from underground mines and the increased use of CH4 collected from degasification systems.
  • Methane emissions from manure management increased by 68.0 percent since 1990, from 31.5 Tg CO2 Eq. in 1990 to 52.9 Tg CO2 Eq. in 2012. The majority of this increase was from swine and dairy cow manure, since the general trend in manure management is one of increasing use of liquid systems, which tends to produce greater CH4 emissions. The increase in liquid systems is the combined result of a shift to larger facilities, and to facilities in the West and Southwest, all of which tend to use liquid systems. Also, new regulations limiting the application of manure nutrients have shifted manure management practices at smaller dairies from daily spread to manure managed and stored on site.


2012 U.S. Energy Consumption by Energy Source


Recent Trends in Various U.S. Data (Index 1990 = 100)

API welcomes EPA report on falling U.S. emissions: The Environmental Protection Agency’s (EPA) latest report shows that natural gas continues to help shrink America’s carbon footprint, said API Spokesman Zachary Cikanek.

“America is leading the world in reducing greenhouse gasses thanks, in part, to the revolution in natural gas production,” said Cikanek. “This latest report shows that emissions dropped an additional 3.4 percent from 2011 to 2012, and emissions are down 10 percent since 2005. Innovations in hydraulic fracturing and horizontal drilling have helped make the U.S. the largest producer of natural gas in the world, and these technologies are a great example of how we can grow the economy, create jobs, and protect the environment.”

The American Gas Association (AGA) today applauded the announcement by the U.S. Environmental Protection Agency (EPA) that estimates of emissions from our nation’s natural gas delivery system continue their declining trend. The 19th Annual Inventory of U.S. Greenhouse Gas Emissions and Sinks affirms that “the major contributors to the decrease in emissions from 2011-2012 were the decrease in energy consumption across all sectors in the U.S. economy, and the decrease in carbon intensity for electricity generation due to fuel switching from coal to natural gas.”

Limited Time - Free Offer

Subscribe to our Newsletter

Question of the Week

Each week, we ask readers for their opinion on an important current topic in the Smart Energy industry. We publish the results in Publisher’s Note. Please Click below to read details and respond.

 Click here to see the details. 

Quick Menu


Category Blog

News By Category

About Us



Contact Us

Crescent Electric Supply Company

cree cr6 led ad


Contact Us for Advertising Opportunities in this website. We have agressive pricing models currently as we build our readership. Contact us to find out current monthly traffic counts and to become a sponsor / advertiser, today!


S5 Box