Tag Archives: Department of Energy

The Importance of Baseload Generation and Real-Time Control to Grid Stability and Reliability

On 23 August 2017, the Department of Energy (DOE) issued a report entitled, “Staff Report to the Secretary on Energy Markets and Reliability.” In his cover letter, Energy Secretary Rick Perry notes:

“It is apparent that in today’s competitive markets certain regulations and subsidies are having a large impact on the functioning of markets, and thereby challenging our power generation mix. It is important for policy makers to consider their intended and unintended effects.”

Among the consequences of the national push to implement new generation capacity from variable renewable energy (VRE) resources (i.e., wind & solar) are: (1) increasing grid perturbations due to the variability of the output from VRE generators, and (2) early retirement of many baseload generating plants because of several factors, including the desire of many states to meet their energy demand with a generating portfolio containing a greater percentage of VRE generators. Grid perturbations can challenge the reliability of the U.S. bulk power systems that comprise our national electrical grid. The reduction of baseload capacity reduces the resilience of the bulk power system and its ability dampen these perturbations.

The DOE staff report contains the following typical daily load curve. Baseload plants include nuclear and coal that operate at high capacity factor and generally do not maneuver in response to a change in demand. The intermediate load is supplied by a mix of generators, including VRE generators, which typically operate at relatively low capacity factors. The peak load generators typically are natural gas power plants that can maneuver or be cycled (i.e., on / off) as needed to meet short-term load demand. The operating reserve is delivered by a combination of power plants that can be reliably dispatched if needed.

The trends in new generation additions and old generation retirements is summarized in the following graphic from the DOE staff report.

Here you can see that recent additions (since 2006) have focused on VRE generators (wind and solar) plus some new natural gas generators. In that same period, retirements have focused on oil, coal and nuclear generators, which likely were baseload generators.

The DOE staff report noted that continued closure of baseload plants puts areas of the country at greater risk of power outages. It offered a list of policy recommendations to reverse the trend, including providing power pricing advantages for baseload plants to continue operating, and speeding up and reducing costs for permitting for baseload power and transmission projects.

Regarding energy storage, the DOE staff report states the following in Section 4.1.3:

“Energy storage will be critical in the future if higher levels of VRE are deployed on the grid and require additional balancing of energy supply and demand in real time.”

“DOE has been investing in energy storage technology development for two decades, and major private investment is now active in commercializing and the beginnings of early deployment of grid-level storage, including within microgrids.”

Options for energy storage are identified in the DOE staff report.

You can download the DOE staff report to the Secretary and Secretary Perry’s cover letter here:


Lyncean members should recall our 2 August 2017 meeting and the presentation by Patrick Lee entitled, “A fast, flexible & coordinated control technology for the electric grid of the future.” This presentation described work by Sempra Energy and its subsidiary company PXiSE Energy Solutions to address the challenges to grid stability caused by VRE generators.   An effective solution has been demonstrated by adding energy storage and managing the combined output of the VER generators and the energy storage devices in real-time to match supply and demand and help stabilize the grid. This integrated solution, with energy storage plus real-time automated controls, appears to be broadly applicable to VRE generators and offers the promise, especially in Hawaii and California, for resilient and reliable electrical grids even with a high percentage of VRE generators in the state’s generation portfolio.

You can download Patrick Lee’s 2 August 2017 presentation to the Lyncean Group of San Diego at the following link:






Bio-fuel at Less Than Half the Price

1.  New process for manufacturing bio-fuel

The Joint BioEnergy Institute (JBEI) is a Department of Energy (DOE) bioenergy research center dedicated to developing advanced bio-fuels, which are liquid fuels derived from the solar energy stored in plant biomass. Such fuels currently are replacing gasoline, diesel and jet fuels in selected applications.

On 1 July 2016, a team of Lawrence Berkeley National Laboratory (LBNL) and Sandia National Laboratories (SNL) scientists working at JBEI published a paper entitled, “CO2 enabled process integration for the production of cellulosic ethanol using bionic liquids.” The new process reported in this paper greatly simplifies the industrial manufacturing of bio-fuel and significantly reduces waste stream volume and toxicity as well as manufacturing cost.

The abstract provides further information:

“There is a clear and unmet need for a robust and affordable biomass conversion technology that can process a wide range of biomass feedstocks and produce high yields of fermentable sugars and bio-fuels with minimal intervention between unit operations. The lower microbial toxicity of recently developed renewable ionic liquids (ILs), or bionic liquids (BILs), helps overcome the challenges associated with the integration of pretreatment with enzymatic saccharification and microbial fermentation. However, the most effective BILs known to date for biomass pretreatment form extremely basic pH solutions in the presence of water, and therefore require neutralization before the pH range is acceptable for the enzymes and microbes used to complete the biomass conversion process. Neutralization using acids creates unwanted secondary effects that are problematic for efficient and cost-effective biorefinery operations using either continuous or batch modes.

We demonstrate a novel approach that addresses these challenges through the use of gaseous carbon dioxide to reversibly control the pH mismatch. This approach enables the realization of an integrated biomass conversion process (i.e., “single pot”) that eliminates the need for intermediate washing and/or separation steps. A preliminary technoeconomic analysis indicates that this integrated approach could reduce production costs by 50–65% compared to previous IL biomass conversion methods studied.”

 Regarding the above abstract, here are a couple of useful definitions:

  • Ionic liquids: powerful solvents composed entirely of paired ions that can be used to dissolve cellulosic biomass into sugars for fermentation.
  • Enzymatic saccharification: breaking complex carbohydrates such as starch or cellulose into their monosaccharide (carbohydrate) components, which are the simplest carbohydrates, also known as single sugars.

The paper was published on-line in the journal, Energy and Environmental Sciences, which you can access via the following link:


Let’s hope they’re right about the significant cost reduction for bio-fuel production.

2.  Operational use of bio-fuel

One factor limiting the wide-scale use of bio-fuel is its higher price relative to the conventional fossil fuels it is intended to replace. The prospect for significantly lower bio-fuel prices comes at a time when operational use of bio-fuel is expanding, particularly in commercial airlines and in the U.S. Department of Defense (DoD). These bio-fuel users want advanced bio-fuels that are “drop-in” replacements to traditional gasoline, diesel, or jet fuel. This means that the advanced bio-fuels need to be compatible with the existing fuel distribution and storage infrastructure and run satisfactorily in the intended facilities and vehicles without introducing significant operational or maintenance / repair / overhaul (MRO) constraints.

You will find a fact sheet on the DoD bio-fuel program at the following link:


The “drop in” concept can be difficult to achieve because a bio-fuel may have different energy content and properties than the petroleum fuel it is intended to replace. You can find a Department of Energy (DOE) fuel properties comparison chart at the following link:


Another increasingly important factor affecting the deployment of bio-fuels is that the “water footprint” involved in growing the biomass needed for bio-fuel production and then producing the bio-fuel is considerably greater than the water footprint for conventional hydrocarbon fuel extraction and production.

 A.  Commercial airline use of bio-fuel:

Commercial airlines became increasingly interested in alternative fuels after worldwide oil prices peaked near $140 in 2008 and remained high until 2014.

A 2009 Rand Corporation technical report, “Near-term Feasibility of Alternative Jet Fuels,” provides a good overview of issues and timescales associated with employment of bio-fuels in the commercial aviation industry. Important findings included:

  • Drop-in” fuels have considerable advantages over other alternatives as practical replacements for petroleum-based aviation fuel.
  • Alcohols do not offer direct benefits to aviation, primarily because high vapor pressure poses problems for high-altitude flight and safe fuel handling. In addition, the reduced energy density of alcohols relative to petroleum-based aviation fuel would substantially reduced aircraft operating capabilities and would be less energy efficient.
  • Biodiesel and biokerosene, collectively known as FAMEs, are not appropriate for use in aviation, primarily because they leave deposits at the high temperatures found in aircraft engines, freeze at higher temperatures than petroleum-based fuel, and break down during storage

You can download this Rand report at the following link


After almost two years of collaboration with member airlines and strategic partners, the International Air Transport Association (IATA) published the report, “IATA Guidance Material for Biojet Fuel Management,” in November 2012. A key finding in this document is the following:

“To be acceptable to Civil Aviation Authorities, aviation turbine fuel must meet strict chemical and physical criteria. There exist several specifications that authorities refer to when describing acceptable conventional jet fuel such as ASTM D1655 and Def Stan 91-91. At the time of issue, blends of up to 50% biojet fuel produced through either the Fischer-Tropsch (FT) process or the hydroprocessing of oils and fats (HEFA – hydroprocessed esters and fatty acids) are acceptable for use under these specifications, but must first be certified under ASTM D7566. Once the blend has demonstrated compliance with the relevant product specifications, it may be regarded as equivalent to conventional jet fuel in most applications.“

You can download this IATA document at the following link:


In 2011, KLM flew the world’s first commercial bio-fuel flight, carrying passengers from Amsterdam to Paris. Also in 2011, Aeromexico flew the world’s first bio-fuel trans-Atlantic revenue passenger flight, from Mexico City to Madrid.

In March 2015, United Airlines (UA) inaugurated use of bio-fuel on flights between Los Angeles (LAX) and San Francisco (SFO). Eventually, UA plans to expand the use of bio-fuel to all flights operating from LAX. UA is the first U.S. airline to use renewable fuel for regular commercial operation.

Many other airlines worldwide are in various stages of bio-fuel testing and operational use.

B.  U.S. Navy use of bio-fuel:

The Navy is deploying bio-fuel in shore facilities, aircraft, and surface ships. Navy Secretary Ray Mabus has established a goal to replace half of the Navy’s conventional fuel supply with renewables by 2020.

In 2012, the Navy experimented with a 50:50 blend of traditional petroleum-based fuel and biofuel made from waste cooking oil and algae oil.   This blend was used successfully on about 40 U.S. surface ships that participated in the Rim of the Pacific (RIMPAC) exercise with ships of other nations. The cost of pure bio-fuel fuel for this demonstration was about $26.00 per gallon, compared to about $3.50 per gallon for conventional fuel at that time.

In 2016, the Navy established the “Great Green Fleet” (GGF) as a year-long initiative to demonstrate the Navy’s ability to transform its energy use.

Great Green Fleet logo          Source: U.S. Navy

The Navy described this initiative as follows:

“The centerpiece of the Great Green Fleet is a Carrier Strike Group (CSG) that deploys on alternative fuels, including nuclear power for the carrier and a blend of advanced bio-fuel made from beef fat and traditional petroleum for its escort ships. These bio-fuels have been procured by DON (Department of Navy) at prices that are on par with conventional fuels, as required by law, and are certified as “drop-in” replacements that require no engine modifications or changes to operational procedures.”

Deployment of the Great Green Fleet started in January 2016 with the deployment of Strike Group 3 and its flagship, the nuclear-powered aircraft carrier USS John C. Stennis. The conventionally-powered ships in the Strike Group are using a blend of 10% bio-fuel and 90% petroleum. The Navy originally aimed for a 50:50 ratio, but the cost was too high. The Navy purchased about 78 million gallons of blended bio-fuel for the Great Green Fleet at a price of $2.05 per gallon.

C.  U.S. Air Force use of bio-fuel:

The USAF has a goal of meeting half its domestic fuel needs with alternative sources by 2016, including aviation fuel.

The Air Force has been testing different blends of jet fuel and biofuels known generically as Hydrotreated Renewable Jet (HRJ). This class of fuel uses triglycerides and free fatty acids from plant oils and animal fats as the feedstock that is processed to create a hydrocarbon aviation fuel.

To meet its energy plan, the USAF plans to use a blend that combines military-grade fuel known as JP-8 with up to 50 percent HRJ. The Air Force also has certified a 50:50 blend of Fisher-Tropsch synthetic kerosene and conventional JP-8 jet fuel across its fleet.

The Air Force Civil Engineer Support Agency (AFCESA), headquartered at Tyndall Air Force Base, Florida is responsible for certifying the USAF aviation fuel infrastructure to ensure its readiness to deploy blended JP-8/bio-fuel.


U.S. Reliance on Non-Fuel Mineral Imports

The U.S. Geologic Survey produces a series of mineral commodity annual reports and individual commodity data sheets. The web page for the index to these reports and data sheets is at the following link:


One particularly interesting document, with a very dull sounding title, is, Mineral Commodity Summaries 2015, which you can download for free at the following link:


This USGS report starts by putting the non-fuel mineral business sector in context with the greater U.S. economy. In the USGS chart below, you can see that the non-fuel mineral business sector makes up 13.5% of the U.S. economy. By dollar volume, net imports of processed mineral materials make up only a small portion (about 1.6%) of the non-fuel mineral business.

USGS role of minerals in the economy

In the, Mineral Commodity Summaries 2015, USGS also identified the U.S. reliance on non-fuel minerals imports. Their chart for 2014 is reproduced below.

USGS Net Import Reliance

Many of the above non-fuel minerals have very important uses in high-value products created in other business sectors.  A good summary table on this matter appears in the National Academies Press report entitled, Emerging Workforce Trends in the U.S. Energy and Mining Industries: A Call to Action, published in August 2015. You can view or download this report for free at the following link:


In this report, refer to Table 2.5, Common or Essential Products and Some of Their Mineral Components.

Among the minerals with very important roles in modern electrical and electronic components and advanced metals is the family of rare earths, which is comprised of the 17 elements highlighted in the periodic table, below:

  • the 15 members of the Lanthanide series from 57La (Lanthanum) to 71Lu (Lutetium), and
  • the two Transitional elements 21Sc (Scandium) and 39Y (Yttrium).

Periodic Table - Rare Earths

Source: www.rareelementresources.com/

In the above 2014 import reliance chart, USGS reported that the U.S. continued to be a net importer of rare earth minerals (overall, 59% reliant), and that for Scandium the U.S was 100% reliant on imports.

In the Mineral Commodity Summaries 2015, USGS reported the following usage of rare earth minerals in the U.S.:

  • General uses: catalysts, 60%; metallurgical applications and alloys, 10%; permanent magnets, 10%; glass polishing, 10%; and other, 10%.
  • Scandium principal uses: solid oxide fuel cells (SOFCs) and aluminum-scandium alloys. Other uses are in ceramics, electronics, lasers, lighting, and radioactive isotopes used as a tracing agent in oil refining

China became the world’s dominant producer of rare earths in the 1990s, replacing U.S. domestic producers, none of which could not compete economically with the lower prices offered by the Chinese producers.

On March 22, 2015, the CBS TV show 60 Minutes featured a segment on the importance of rare earth elements and underscored the need to ensure a domestic supply chain of these critical minerals. You can view this segment at the following link:


In December 2011, the U.S. Department of Energy (DOE) issued a report entitled Critical Materials Strategy, which you can download for free at the following link:


The summary results of the DOE “criticality assessment” are reproduced below

“Sixteen elements were assessed for criticality in wind turbines, EVs (electric vehicles), PV (photovoltaic) cells and fluorescent lighting. The methodology used was adapted from one developed by the National Academy of Sciences. The criticality assessment was framed in two dimensions: importance to clean energy and supply risk. Five rare earth elements (REEs)—dysprosium, terbium, europium, neodymium and yttrium—were found to be critical in the short term (present–2015). These five REEs are used in magnets for wind turbines and electric vehicles or phosphors in energy-efficient lighting. Other elements—cerium, indium, lanthanum and tellurium—were found to be near-critical. Between the short term and the medium term (2015– 2025), the importance to clean energy and supply risk shift for some materials (Figures ES-1 and ES-2).”

DOE Critical Materials Strategy

While the results of the DOE criticality assessment focused on importance to the energy sector, the identified mineral shortages will impact all business sectors that depend on these minerals, including consumer electronics and national defense.

Further insight on the importance of rare earths is provided by an annual report to the Senate Select Committee on Intelligence entitled, U.S. Intelligence Community Worldwide Threat Assessment Statement for the Record. The report delivered on March 12, 2013 highlighted the national security threat presented by China’s monopoly on rare earth elements. You can download that report at the following link:


The 2013 threat assessment offered the following perspective on the strategic importance of rare earth minerals:

“Rare earth elements (REE) are essential to civilian and military technologies and to the 21st century global economy, including development of green technologies and advanced defense systems. China holds a commanding monopoly over world REE supplies, controlling about 95 percent of mined production and refining. China’s dominance and policies on pricing and exports are leading other countries to pursue mitigation strategies, but those strategies probably will have only limited impact within the next five years and will almost certainly not end Chinese REE dominance.”

 While the above focus has been on rare earths, the discussion serves to illustrate that the U.S. is dependent on importing many minerals that are very important to the national economy.





Radioisotope Thermoelectric Generators (RTG) for Spacecraft: History and Current U.S. Pu-238 Production Status

Radioisotope Thermoelectric Generators (RTG), also called Radioisotope Power Systems (RTS), commonly use non-weapons grade Plutonium 238 (Pu-238) to generate electric power and heat for National Aeronautics and Space Administration (NASA) spacecraft when solar energy and batteries are not adequate for the intended mission.

Approximately 300 kg (661 lb) of Pu-238 was produced by the Department of Energy (DOE) at the Savannah River Site between 1959 – 1988. After U.S production stopped, the U.S. purchased Pu-238 from Russia until that source of supply ended in 2010.

Limited production of new Pu-238 in the U.S re-started in 2013 using the process shown below. This effort is partially funded by NASA.  Eventually, production capacity will be about 1.5 kg (3.3 lb) Pu-238 per year. The roles of the DOE national laboratories involved in this production process are as follows:

  • Idaho National Engineering Lab (INEL):
    • Store the Neptunium dioxide (NpO2) feed stock
    • Deliver feed stock as needed to ORNL
    • Irradiate targets provided by ORNL in the Advanced Test Reactor (ATR)
    • Return irradiated targets to ORNL for processing
  • Oak Ridge National Lab (ORNL):
    • Manufacture targets
    • Ship some targets to INEL for irradiation
    • Irradiate the remaining targets in the High Flux Isotope Reactor (HFIR)
    • Process all irradiated targets to recover and purify Pu-238
    • Convert Pu-238 to oxide and deliver as needed to LANL
  • Los Alamos National Lab (LANL):
    • Manufacture the Pu-238 fuel pellets for use in RTGs

Pu-238 production process

Diagram source: Ralph L McNutt, Jr, Johns Hopkins University APL, 2014

The U.S. has an existing inventory of  about 35 kg (77 lb) of Pu-238 of various ages.  About half is young enough to meet the power specifications of planned NASA spacecraft. The remaining stock is more than 20 years old, has decayed significantly since it was produced, and does not meet specifications.   The existing inventory will be blended with newly produced Pu-238 to extend the usable inventory. To get the energy density needed for space missions while extending the supply of Pu-238, DOE and NASA plan to blend “old” Pu-238 with newly produced Pu-238 in 2:1 proportions.

NASA slowly has been developing an Advanced Stirling Radioisotope Generator (ASRG), which should be capable of producing about four times the power of older RTGs per unit of Pu-238. However, the ASRG produces less waste heat, which can be used productively to warm electronics in the interior of a spacecraft, such as the Mars rover Curiosity. The ASRG may not be available in time for the next space mission requiring an RTG power source, in which case an existing RTG design will be used.

Read a history of RTGs and more information on current U.S. Pu-238 production status in a 2014 presentation by Ralph L McNutt, Jr, at the following link:


9 February 2016 Update

On 22 December 2015, DOE reported production of 50 grams of new Pu-238.

DOE reported that it plans to set an initial production target of 300 – 400 grams (about 12 ounces) of Pu-238 per year. After implementing greater automation and scaling up the process, ORNL expects to reach the the production target of 1.5 kg (3.3 lb) Pu-238 per year.

The next NASA mission that will use an RTG is the Mars 2020 rover, which will use the same Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) as used on NASA’s Mars rover Curiosity. MMRTG can provide about 110 watts of electrical power to a spacecraft and its science instruments at the beginning of a mission.

You can read the ORNL announcement of initial Pu-238 production at the following link:



History of the DOE National Laboratories

Many at SAIC worked at or for one or more DOE national laboratories at some point in their careers.   The following link to the DOE Office of Scientific & Technical Information (OSTI) web site provides links to other web sites with historical information on the various national labs.


For example, on this OSTI web page, you can select the Idaho National Laboratory link, and a pop-up menu will display the available documents.  If you select, “Proving the Principle: A History of the Idaho Engineering and Environmental Laboratory, 1949 – 1999,” this will take you to an INL web site that includes a 25 chapter history + a 2000 – 2010 addendum, all organized for chapter-by-chapter web access.

I hope you find some something of interest via the OSTI website.