Natural Gas Appliances and Global Warming

For several years the U.S. Department of Energy has been promoting the use of induction for home cooking. Conventional residential cooking tops typically use gas or resistance electric heating elements, (the ubiquitous coil) to heat food.  The government estimates that gas stoves are approximately 32% efficient in their energy use and electric stoves are 75-80% efficient.  Residential induction burners consist of an electromagnetic coil that creates a magnetic field when turned on. Compatible cookware is heated when it is within the magnetic according to the DOE induction cooking 85% efficient. Less heat is lost to the surrounding air, providing an additional energy efficiency benefit by reducing the workload for air conditioning equipment. A cooler cooking top surface also makes induction cook tops safer to work with than other types of cooking tops. Finally, because the cookware itself is the source of heat, it reaches desired temperatures more quickly and provides faster cook times.

I had always dreamed of a kitchen with a commercial or commercial style stove. When I had saved up the money to upgrade my kitchen, I realized that the kitchen centerpiece stove was not my best choice. First of all, it is a warming world and those stove throw off lots of heat, second I live in a rural area where natural gas (methane) is not available, instead we have a propane tank and third commercial stoves are simply not good at low simmer, my preferred cooking style. I make lots of sauces, gravy, stews and soups. Gas burners (especially propane with its three carbons) burn too hot. So, in 2018 when I updated my kitchen I installed an induction cook top. I have been amazingly happy with that choice. The cooking is all I had hoped. What I had not anticipated is how easy and fast it is to clean, and the bad kitty cannot accidentally turn it on.

Now scientists are taking a closer look at cooking with gas. Natural gas is a popular fuel choice for home cooking and has always been considered better than conventional electric. It has the reputation that “real cooks” use natural gas. Nationally, over 40 million homes (about a third) cook with gas. Natural gas appliances release methane and other pollutants through leaks and incomplete combustion. These appliances warm the planet in two ways: generating carbon dioxide by burning natural gas as a fuel and leaking unburned methane into the air. A recent Stanford University study found that the methane leaking from natural gas-burning stoves emit up to 1.3 % of the gas they use as unburned methane.

According to the U.S. EPA, methane is the second most prevalent greenhouse gas and accounted for about 10% of all U.S. greenhouse gas emissions from human activities. Methane is emitted by natural sources such as wetlands and the breakdown of organic material, as well as from leakage from natural gas systems, growing rice, waste disposal and the raising of livestock. Methane is a powerful greenhouse gas and is 25 times more effective than carbon dioxide at trapping heat over a 100-year period. While it does occur naturally, major human-generated sources include landfills, refineries, oil and gas fields, natural gas infrastructure, dairies and wastewater treatment plants.

This work came out of Dr. Jackson’s lab at Stanford University where they are working to measure and reduce greenhouse gas emissions through the Global Carbon Project (globalcarbonproject.org), which Jackson chairs. Some of their work is directly aimed at measuring and reducing methane emissions from oil and gas wells, city streets, and homes and buildings. According to Dr. Jackson and his colleagues, curbing methane emissions will require reducing fossil fuel use and controlling fugitive emissions such as leaks from pipelines and wells, as well as changes to the way we feed cattle, grow rice and eat. “We’ll need to eat less meat and reduce emissions associated with cattle and rice farming,” Dr. Jackson said, “and replace oil and natural gas in our cars and homes.”

The scientists measured methane and nitrogen oxides released in 53 homes in California- not the biggest of sample. Their sample group included 18 brands of gas cooktops and stoves ranging in age from 3 to 30 years old .Measurements were taken during combustion, ignition, extinguishment, and also while the appliance was off.  

The scientist found no relationship between the age or cost of a stove and its emissions. What they did find that more than three-quarters of methane emissions occurred while stoves were off, suggesting that gas fittings and connections to the stove and in-home gas lines are responsible for most emissions, regardless of how much the stove is used. They should have probably examined the age of the interior piping and fittings in the home, but that was not part of the study. California does not require a building permit when you replace gas appliances the way we do here. So the fittings in California are not tested regularly over time.

The scientists found the highest emitters were cooktops that used a pilot light instead of a built-in electronic sparker. Methane emissions from the puffs of gas emitted while igniting and extinguishing a burner were on average equivalent to the amount of unburned methane emitted during about 10 minutes of cooking with the burner.

Larger stoves (those trophy kitchen appliances )tended to emit higher rates of nitric oxides. The scientists estimated that people who don’t use their range hoods or who have poor ventilation can surpass the EPA’s guidelines for 1-hour exposure to nitrogen dioxide outdoors (there are no indoor standards) within a few minutes of stove usage, particularly in smaller kitchens.

Dr. Jackson encourages switching to electric stoves to cut greenhouse gas emissions and indoor air pollution. I switched to induction to get fabulous cooking,  easy cleanup and energy efficiency. I  maintain propane in my home to power my backup generator, a propane furnace, a gas fireplace (I'm thinking about it) and hot water heater. Without electricity I have no water-my well pump does not work, my air heat pumps do not work, and all my kitchen appliances and freezer go down. We have lost power for several days after a storm in the winter and once in the summer. Because I have the generator and  backup systems, my pipes did not burst, my septic pump continued to operate and life went on.

Methane in the Atmosphere Rises

R B Jackson, M Saunois, P Bousquet , J G Canadell, B Poulter, A R Stavert , P Bergamaschi, Y Niwa , A Segers and A Tsuruta: Increasing anthropogenic methane emissions arise equally from agricultural and fossil fuel sources, Environ. Res. Lett. 15 (2020) 071002 https://iopscience.iop.org/article/10.1088/1748-9326/ab9ed2/pdf.


As you have probably heard or read the lock downs associated with the Covid-19 pandemic has reduced global carbon emissions, albeit temporarily. However, Scientists at the Stanford’s School of Earth Energy and Environmental Sciences believe it is unlikely that methane levels in the environment have seen the same reduction because many of the sources of methane have continued unabated. The paper cited above tells the story or rising methane levels. Methane levels in the atmosphere have risen since 2000. We care about methane because climate scientists estimate that the gas is responsible for about one quarter of the global warming that has happened since industrialization.

According to the paper cited above the amount of methane in Earth’s atmosphere continues to rise. Concentrations of methane now exceed 1875 parts per billion, about 2.5 times as much as was in the atmosphere in the 1850s. The researchers synthesized all known data about methane from the US EPA’s emissions inventories, atmospheric measurements, and models to assemble a global “methane budget” that details which processes add the gas to the atmosphere and which remove it.

 

from the Global Carbon Project

According to their study, wetlands contributed 30% of global methane emissions, with oil, gas, and coal activities accounting for 20%. Agriculture, including enteric fermentation (cow belching), manure management, and rice cultivation, made up 24% of emissions, and landfill gas contributed 11%. Sixty-four percent of methane emissions came from the tropical regions of South America, Asia, and Africa, with temperate regions accounting for 32% and the Arctic contributing 4%.

Methane emissions rose most sharply in Africa and the Middle East; China; and South Asia and Oceania. Each of these three regions increased emissions by an estimated 10 to 15 million tons per year during the study period. The United States followed behind, increasing methane emissions by 4.5 million tons, mostly due to more natural gas drilling, distribution and consumption.Europe was the only region where methane emissions decreased over the study period, attributed to reductions chemical manufacturing and growing food more efficiently with better management of manure and landfills. 

According to Dr. Jackson and his colleagues, curbing methane emissions will require reducing fossil fuel use and controlling fugitive emissions such as leaks from pipelines and wells, as well as changes to the way we feed cattle, grow rice and eat. “We’ll need to eat less meat and reduce emissions associated with cattle and rice farming,” Dr. Jackson said, “and replace oil and natural gas in our cars and homes.”

Rob Jackson is Stanford’s Michelle and Kevin Douglas Provostial Professor. Dr. Jackson and his lab examine the many ways people affect the Earth.  They're currently examining the effects of climate change and droughts on forest and grassland ecosystems. They are also working to measure and reduce greenhouse gas emissions through the Global Carbon Project (globalcarbonproject.org), which Jackson chairs; examples of new research Rob leads include establishing a global network of methane tower measurements at more than 80 sites worldwide and measuring and reducing methane emissions from oil and gas wells, city streets, and homes and buildings.

Their work has real practical applications for reducing the emission of greenhouse gases, though he admits Human driven emissions are in many ways easier to pin down than those from natural sources.

Methane Regulation Coming Our Way

from EPA

Last Wednesday, the U.S. Environmental Protection Agency (EPA) officially announced the next set of regulations for the United States to address climate change; EPA will set standards for methane and VOC emissions from new and modified oil and gas wells, and natural gas processing and transmission plants. By summer of 2015 EPA will issue a proposed rule and a final rule will follow in 2016. As with the power sector, EPA plans to first regulate new methane emissions, then circle back and regulate the existing sources of methane emissions.

Regulation of existing oil and gas wells will begin ahead of EPA regulations for the oil and gas industry. Using the Department of Interior’s Bureau of Land Management (BLM), the Administration will begin tightening the regulations on existing oil and gas wells by toughening the standards for operating gas and oil wells on federal land. The new standards will be designed to reduce venting, flaring, and leaks of natural gas, which is primarily methane, from these oil and gas wells. These standards, to be proposed this spring, will address both new and existing oil and gas wells on public lands and will serve as a test run on regulating existing oil and gas wells.

The Department of Transportation’s Pipeline and Hazardous Materials Safety Administration will propose natural gas pipeline safety standards in 2015 aimed at reducing leaks and releases from pipelines. The Department of Energy (DOE) will develop and demonstrate more cost-effective technologies to detect and reduce losses from natural gas transmission and distribution systems that is believed to represent over 22% of methane gas losses in the sector. The DOE effort will include efforts to repair leaks and develop the next generation of compressors. According to the EPA the President’s budget will propose $10 million to launch a program at DOE to examine the scope of leaks from gas distribution systems, pipelines and compressor plants to examine their contribution to global warming.

Two years ago Robert B. Jackson, Professor of Global Environmental Change at Duke University and Nathan Phillips, associate professor at Boston University Department of Earth and Environment collaborated with Robert Ackley of Gas Safety Inc., and Eric Crosson of Picarro Inc., to perform a study of gas leaks in Boston. They mapped the gas leaks under the city using a new, high-precision methane analyzer. The researchers discovered 3,356 leaks. The leaks were found to be associated with old cast-iron underground pipes, infrastructure that had not been maintained. The team went on to document leaks in Washington DC, but EPA wants to quantify the emissions of the entire wholesale and retail distribution system. In addition to the explosion hazard, methane, the primary ingredient of natural gas, is a powerful greenhouse gas that degrades air quality. Leaks in the United States are reported to contribute to $3 billion of lost and unaccounted for natural gas each year.

The White House set a new target for the U.S. to cut methane emissions in the energy sector by 40% to 45% by 2025, compared with 2012 levels. Methane emissions in the energy sector represent only about 30% of the total. Methane emissions come from diverse sources and sectors of the economy, unevenly dispersed across the nation and not well tracked. That is why the EPA wants to begin to better quantify the emissions. There is little hard data on methane emissions; nonetheless, the estimates below are the best available and the Administration has used them to develop the current methane mitigation plan for the energy sector. You’ll note that the methane emissions from natural gas systems has decreased by about 15% from 2005 to 2012 despite the production of natural gas increasing by about 50% during that time period.

Over the last two hundred and fifty years, the concentration of methane in our atmosphere has increased by 151% to 1.8 parts per million. Methane is the primary component in natural gas, methane is emitted to the atmosphere during the production, processing, storage, transmission, and distribution of natural gas and because gas is often found alongside petroleum which is often much more valuable, methane is sometimes vented to the atmosphere rather than captured during oil production. Methane is also produced from the decomposition of human and animal waste as well as garbage and is the major component of landfill gas. Methane is also released from the natural biological process of enteric fermentation which is fermentation that takes place in the digestive systems of animals. In particular, ruminant animals that have two stomachs and eat grasses (cattle, buffalo, sheep, goats, and camels) produce and release methane by “passing gas” from the microbial fermentation that breaks down the grass and hay into soluble products that can be utilized by the animal. To significantly reduce the methane released from enertic fermentation it might be necessary to reduce the cattle and sheep population and the share of the American diet that is beef, lamb and dairy products. Finally, when natural gas and other petroleum products are used as a fuel incomplete combustion releases traces of methane.

According to the Intergovernmental Panel on Climate Change (IPCC), methane is more than 20-25 times more effective as CO2 at trapping heat in the atmosphere. So eventhough it is a much smaller component of the atmosphere, controlling methane emissions is essential to the Administrations plans to address climate change, though unfortunately “addressing” will not stop climate change. If you recall it is the greenhouse effect that is expected to increase the sensitivity of the climate to carbon dioxide, methane and the other greenhouse gases. According to climate scientists we have passed the tipping point and there is no stopping the climate trajectory predicted by the models that have been developed to understand and predict the climate of earth. However, detecting and reducing gas leaks are critical not only for reducing greenhouse gas emissions, but also for improving air quality and consumer safety, and saving consumers money.

from EPA

President Obama to Reduce Methane Emissions

On Friday the Whitehouse announced that the President, will continue to fight against climate change using executive fiat. The next step for the White House climate plan, originally introduced in a speech at Georgetown University in June 2013, is an “interagency methane strategy.” Towards this goal, the Whitehouse is directing federal agencies to clamp down on emissions of methane, a greenhouse gas, though U.S. methane emissions have fallen 11% since 1990.

data from US EPA

According to the Intergovernmental Panel on Climate Change (IPCC), methane is more than 20 times as effective as CO2 at trapping heat in the atmosphere. If you recall it is the greenhouse effect that is expected to increase the sensitivity of the climate to carbon dioxide, methane and the other greenhouse gases. Though in its September 2013 report the IPCC eliminated attempts to estimate the “most likely” sensitivity of the climate to the expected manmade doubling of the carbon dioxide concentrations in the atmosphere because according to British climate scientist Nic Lewis “the best observational evidence indicates our climate is considerably less sensitive to greenhouse gases than climate scientists had previously thought.” All the climate models had failed to predict that for the last 15 years there has been essentially no net warming. Global Warming has been having what the IPCC calls a hiatus.

Over the last two hundred and fifty years, the concentration of methane in our atmosphere has increased by 151% to 1.8 parts per million. Methane is the primary component in natural gas, methane is emitted to the atmosphere during the production, processing, storage, transmission, and distribution of natural gas and because gas is often found alongside petroleum which is much more valuable, methane is sometimes vented to the atmosphere rather than captured during oil production. Methane is also produced from the decomposition of human and animal waste as well as garbage and is the major component of landfill gas. Methane is also released from the natural biological process of enteric fermentation which is fermentation that takes place in the digestive systems of animals. In particular, ruminant animals that have two stomachs and eat grasses (cattle, buffalo, sheep, goats, and camels) produce and release methane from the microbial fermentation that breaks down the grass and hay into soluble products that can be utilized by the animal. Also, when natural gas and other petroleum products are used as a fuel incomplete combustion releases traces of methane.

Methane emissions come from diverse sources and sectors of the economy, unevenly dispersed across the landscape and not well tracked. These uncertainties have resulted in estimates of current and projected methane emissions by simplified models and rules of thumb for the source of methane emissions. Nonetheless, the estimates below are the best available and the Administration has launched a methane mitigation plan.

The President’s Strategy to Reduce Methane Emissions targets reductions in methane emissions from landfills, coal mining, and agriculture, and oil and gas systems that include action on four fronts:

1. Landfills: This summer, the EPA will propose regulation to reduce methane from new landfills and begin the process to tighten the methane standards for existing landfills.
2. Coal Mines: In April 2014, the Department of the Interior, Bureau of Land Management will begin the process of developing a program for the capture and disposal of waste mine methane on lands leased by the Federal government. 
3. Agriculture: In June 2014, in partnership with the dairy industry, the U. S. Department of Agriculture, the EPA and U.S. Department of Energy will jointly release a “Biogas Roadmap” outlining voluntary strategies to reduce U.S. dairy sector greenhouse gas emissions by 25 % by 2020. Maybe the administration will reduce the U.S. consumption of dairy products, beef, buffalo, sheep and goats and thus reduce the herds of rumens. 
4. Oil and Gas: This spring EPA will assess potential sources of methane and other greenhouse gas emissions from the oil and gas industry and in the fall of 2014, EPA will determine how best to pursue further methane reductions from these sources. EPA is expected to develop additional regulations if necessary by the end of 2016. Later this year, the Bureau of Land Management will update the rules to reduce venting and flaring from oil and gas production on public lands. In addition the Administration will identify “downstream” methane reduction opportunities. Through the Natural Gas STAR program, EPA will work with the industry to expand voluntary efforts to reduce methane emissions.

One downstream area for reduction of methane is our natural gas distribution systems. In 2012 and 2013 two scientists mapped the gas leaks under Boston and Washington DC using a new, high-precision methane analyzer provided by Picarro installed in a GPS-equipped car. They found that there were approximately 4.3 leaks per mile of street in both cities. Levels of methane in the surface air on some streets exceeded 15 times the normal atmospheric background value.

For some time we have failed to maintain our unseen infrastructure systems as a way to cut costs. We have failed to maintain and upgrade the oil and gas distribution system. Gas distribution companies are well aware of the leaks in the system. The companies calculate the difference between the gas pumped into the distribution system and what is metered at the end user. This is referred to as "lost and unaccounted-for" gas is often a surcharge on customer bills. These leaks are wasteful, dangerous and a significant source of greenhouse gas released into the environment.

Distribution companies try to prioritize finding and fixing leaks likely to be explosion hazards, where gas is collecting and concentrating and ignore the small losses from deteriorating iron pipe and the deteriorating distribution system in our cities. Natural gas distribution leaks and explosions cause an average of 17 fatalities, 68 injuries, and $133 million in property damage each year, according to the U.S. Pipeline and Hazardous Materials Safety Administration. In 2010 a natural gas pipeline exploded in San Bruno, CA, just south of San Francisco. There was no warning and eight people were killed, 58 were injured and 38 homes, the entire section of a neighborhood, destroyed. In 2011, a leak from an 83-year-old cast-iron main in Allentown, Pa., caused an explosion that killed five people. And just last month a gas explosion killed eight people in East Harlem.

Detecting and reducing gas leaks are critical for reducing greenhouse gas emissions, improving air quality in cities and consumer safety, and ultimately saving future generations of consumers from loss of life, property and wasted money. Right now, repairing our infrastructure will be very expensive, but as the pipes that distribute gas (and the other essential utilities of water, sewer, and electricity) continue to age failure will become more frequent. Infrastructure is the foundation of our economy, connecting businesses, communities, and people, making us a first world country-we need to repair and maintain it.

Natural Gas Leaks-Death and Climate Change

Yellow spikes are methane leaks measured in Boston. From Jackson et. al. 

Two recent studies have documented thousands of gas leaks in Boston and Washington D.C. Last year two scientists, Robert B. Jackson, Professor of Global Environmental Change at Duke University and Nathan Phillips, associate professor at Boston University Department of Earth and Environment collaborated with Robert Ackley of Gas Safety Inc., and Eric Crosson of Picarro Inc., to perform a study of gas leaks in Boston. They mapped the gas leaks under the city using a new, high-precision methane analyzer provided by Picarro installed in a GPS-equipped car. Driving all 785 road miles within city limits, the researchers discovered 3,356 leaks. The leaks were found to be associated with old cast-iron underground pipes, rather than neighborhood socioeconomic indicators. Levels of methane in the surface air on Boston’s streets exceeded 15 times the normal atmospheric background value. Cast iron is often the oldest and leakiest, especially at the joints, although other pipeline materials can also develop leaks.

This past spring, the team replicated the study on the streets of Washington, D.C. The results for the Washington D.C. study have not been published, but preliminary reports indicate that D.C., too, has thousands of leaks from its natural gas distribution system. According to a report in Scientific American, Dr. Jackson stated, the number of leaks per road mile is similar to that of Boston, but has almost twice as many miles of road.

For some time our infrastructure systems have failed to keep pace with the current and expanding needs, and investment in infrastructure had faltered as an unseen way to cut costs. Every four years the American Society of Civil Engineers, ASCE, grades the infrastructure in the United States, from water mains, sewer systems and plants, the electrical grid, the neighborhood streets and the national highway system, dams, rail roads, airports. Infrastructure is the foundation of our economy, connecting businesses, communities, and people, making us a first world country.

In 2013 the grade for energy remained at a D+ despite the boom in gas and oil due to weakness in the distribution systems. Though, the recent booms in oil and gas production could supply the energy demand, we have failed to maintain and upgrade the oil and gas. Gas distribution companies are well aware of the leaks in the system. The companies calculate the difference between the gas pumped into the distribution system and what is metered at the end user. This is referred to as "lost and unaccounted-for" gas is often a surcharge on customer bills. These leaks are wasteful, dangerous and a significant source of greenhouse gas released into the environment.

Distribution companies prioritize finding and fixing leaks likely to be explosion hazards, where gas is collecting and concentrating and ignore the small losses from deteriorating iron pipe. Though sometimes they do not do that well enough. Natural gas distribution leaks and explosions cause an average of 17 fatalities, 68 injuries, and $133 million in property damage each year, according to the U.S. Pipeline and Hazardous Materials Safety Administration. The transportation and distribution systems run into homes and businesses. In 2010 a natural gas pipeline exploded in San Bruno, CA, just south of San Francisco. There was no warning and eight people were killed, 58 were injured and 38 homes, the entire section of a neighborhood, destroyed. The deaths in San Bruno did not change the way we maintain our infrastructure, though the California Public Utilities Commission has proposed a $2.25 billion penalty, which includes a $300 million fine.

According to Dr. Jackson and Phillips detecting and reducing gas leaks are critical for reducing greenhouse gas emissions, improving air quality and consumer safety, and saving consumers money. In addition to the explosion hazard, natural gas also poses a major environmental threat: Methane, the primary ingredient of natural gas, is a powerful greenhouse gas that degrades air quality. Leaks in the United States are reported to contribute to $3 billion of lost and unaccounted for natural gas each year. Included in the details of the White House climate plan, originally introduced in a speech at Georgetown University in June, is an “interagency methane strategy” that examines the scope of leaks from gas wells, pipelines and compressor plants to examine their contribution to global warming.

The White House climate plan was released immediately after the International Energy Agency (IEA) released a series of recommendation for measures that might curtail the rapid growth that has occurred in carbon dioxide emission from fuel combustion that has taken place in the past few decades despite treaties, meetings and conferences. Global greenhouse gas emissions are increasing rapidly and, in May 2013, carbon-dioxide (CO2) levels in the atmosphere exceeded 400 parts per million for the first time in several hundred millennia.

Though mankind has blown through the tipping point in CO2 emissions that was just a decade ago referred to as the point of no return, the IEA is making policy recommendations that might hold the global temperature increase to 2 to 4°C by cutting global CO2 emissions growth so that it does not exceed 38.75 billion metric tonnes from fossil fuels in 2020. These recommendations really fall into two categories, efficiency and maintenance:

• Installing energy efficiency measures in buildings, and requiring increased efficiency in industry and transportation
• Preventing the construction of and limiting use of the least-efficient and dirtiest coal-fired power plants. In addition to increasing the share of power generation from renewable sources (including nuclear) and from natural gas
• Reducing methane released from the processing and distribution of oil and gas by replacing aging infrastructure and improving technology implementation.

Fracking, Burning Shale Gas and the Environment

Our modern society requires power and that is not going to change. The cost of power is a key factor in determining the cost of production, and the cost of living. In the 1990’s natural gas, sold for $2 per million BTUs after peaking in 2005 natural gas is now about $3.50-$4 per million BTUs, with this price and the advances in drilling the extraction of shale gas is viable and profitable. The techniques for fracking first developed in the Barnett shale in the Fort Worth Basin in Texas have been applied to a series of major shale gas deposits that could not have been viable without these advances in drilling and fracking. The Fayetteville shale, the Haynesville shale, the Marcellus shale reserves all in the United States and the Horn River shales in Canada are now accessible at current market costs. At the current rate of natural gas consumption North America is reported to have a 100-year supply of proven, producible reserves and even with expanded use of natural gas, there is more than a generation of currently accessible reserves.at that price we appear to have vast amounts of available natural gas.

Shale sourced natural gas could provide a reliable source of natural gas for our nation in this century. However we need to remember that the gas still is a limited resource and be cautious about what other impacts fracking might have on our other resources. Natural gas is the cleanest of the fossil fuels. Burning natural gas in the place of coal emits fewer harmful pollutants. Methane, the principle component of natural gas, is itself a potent greenhouse gas. Methane has an ability to trap heat almost 21 times more effectively than carbon dioxide. Concern for the potential impact of the release of greenhouse gases and other impacts from shale gas extraction have been raised by various groups. This year researchers at Carnegie Mellon University compared greenhouse gas emissions from the Marcellus Shale region with emissions from coal used for electricity generation. This study estimates the life cycle greenhouse gas (GHG) emissions from the production of Marcellus shale natural gas . The authors found that natural gas from the Marcellus shale had lower life cycle GHG emissions than coal for production of electricity by 20–50% depending upon plant efficiencies and natural gas emissions variability. The significant range in estimates is due to the variations in the ultimate production from a well (more lifetime production reduces GHG emissions) and differences in flaring, construction and transportation how carefully these steps are carried out.

At least in the medium term the environmental impact from power generation will be determined by the efficiency and care of how fuel is obtained, transported, generated and used. Improving efficiency is the low lying fruit that can have an immense impact and should not be ignored while we are busy dreaming of the someday world of renewable energy. Natural gas from shale rock is plentiful in North America. Despite billions of dollars in DOE solar generation loan guarantees the generating capacity of solar power in the nation will continue to be under 5% of power generation. Recent ambitious plans to convert the nation to renewable energy: build nuclear plants and solar and wind farms, were made under the assumption that natural gas prices would average $9 per million BTUs. At that level, electricity prices would have increased to costs of production and living significantly, but wind and nuclear power generation would have been competitive. Now, with natural gas at under $4 per million BTUs and more gas reserves announced each year, many of these projects suddenly look much too expensive and would never happen without mandated renewable portfolio standards and government incentives. The projects that get done will increase the cost of power when those costs are incorporated into the electric rate base.

Power plants can use several methods to convert gas to electricity. One method is to burn the gas in a boiler to produce steam, which is then used by a steam turbine to generate electricity. A more common approach is to burn the gas in a combustion turbine to generate electricity. Another technology that is growing in popularity is to burn the natural gas in a combustion turbine and use the hot combustion turbine exhaust to make steam to drive a steam turbine. This technology is called "combined cycle" or “natural gas combined turbine plants” and achieves a higher efficiency by using the same fuel source twice.

The CO2 emissions from all natural gas plants are less than to those produced by burning coal given the same power output because of the higher heat content of natural gas, and the higher overall efficiency of the gas generation plant relative to a coal-fired plant. Natural gas also allows for smaller ‘distributed generation’ plants, providing flexibility and local autonomy for generation. However, the gas well lifetime, care in obtaining and transporting the gas and the efficiency of the generation plant will determine overall environmental impact of gas power generation on our earth. Although power plants are regulated by federal and state laws to protect human health and the environment, there is a wide variation of environmental impacts associated with power generation technologies and as the Carnegie Mellon researchers found that natural gas from the Marcellus shale and probably all shale gas has lower life cycle GHG emissions than coal for production of electricity significantly better than the current standard.

Though there has been tremendous concern for the potential direct adverse impact that fracking may have on drinking water, geologists and engineers believe that there is little risk that the fracking “water,” a mix chemicals and water, will somehow infiltrate groundwater reserves though a fissure created by the fracking. It is believed though not documented and tested that the intervening layers of rock would prevent a fissure from extending thousands of feet to the water table. Data should be collected to test this belief as part of a careful monitoring and study of fracking and shale gas extraction. There are other risks in how we build wells and fracture the shale. Documented contamination to drinking water wells due to seepage of fracking water into drinking water wells through improperly sealed or abandoned drilling wells must be addressed.

The current regulatory framework concerning hydraulic fracturing, which is the core element in shale gas and tight oil extraction, has a number of gaps that need to be addressed before unlimited fracking takes place. There were several recommendations made in the report of the Shale Gas Subcommittee of the Secretary of Energy Advisory Board. The report had a rational approach to regulation recommending disclosure, testing, evaluation and modification of regulation and practices based on the information and data obtained. It assumes information and data will be gathered and analyzed. That is not being done. The data needs to be collected on a state and provided to the US Geological Survey and US EPA to consolidate on a national level.

Though the energy companies are beginning to gather baseline data for drinking water wells in the areas being fracked, the data collection is neither ongoing nor broad enough. Drilling requires large amounts of water to create a circulating mud that cools the bit and carries the rock cuttings out of the borehole. After drilling, the shale formation is then stimulated by hydraulic fracking, using up to 3 million gallons of water. Data needs to be gathered on the impact to water resources of supplying water for the construction of thousands of wells per year. For gas to flow out of the shale, nearly all of the water injected into the well during fracking must be recovered and disposed of. At under 0.5% by volume, the proprietary chemicals used in fracking total 15,000 gallons in the waste from the typical 3 million gallon hydro fracking job. The chemicals serve to increases the viscosity of the water to a gel-like consistency so that it can carry the propping agent (typically sand) into the fractures to hold them open so that the gas can flow. Determining the proper methods for the safe disposal of the large quantities of this fracking fluid that may also contain contaminants from the geological formation including brines, heavy metals, radionuclides and organic contaminants and monitoring the impact from this disposal must also be done. The deep well injection of the waste in Texas was associated with earthquakes and is believed by scientists to have triggered the earthquakes. The impact of so much waste water on our water resources must be measured and monitored. Finally, care must be taken to avoid degradation of watersheds and streams from the industry itself as large quantities of heavy equipment and supplies are moved on rural roads and placed on concrete pads. The watersheds must be monitored.

Other impacts from shale gas fracking and extraction is watershed impact and surface land damage due to construction of drilling pads, the transport and use of trucks, equipment, gas processing equipment and the creation of access roads in often remote areas. Other possible impacts are air emissions of pollutants and methane, groundwater contamination due to uncontrolled gas or fluid flows due to blowouts or spills, leaking fracturing fluid, and uncontrolled waste water discharge. Fracturing fluids contain hazardous substances, and flow-back in addition contains heavy metals and radioactive materials from the deposit. Experience shows that many accidents happen, which can be harmful to the environment and to human health. Many of these accidents are due to improper sealing of casings or leaking equipment. Furthermore, groundwater contamination by methane, in extreme cases leading to significant methane levels or even explosions from residential drinking water wells and potassium chloride leading to salinization of drinking water aquifer has been reported in the vicinity of some gas wells. The impacts can add up and make as shale formations are developed with a high well density of up to six well pads per square mile. Hydraulic fracturing means jobs and wealth, but the industry needs to develop adequate procedures, techniques and standards to minimize environmental impact and maximize gas recovery. Slow is fast.

Prince William County Landfill and Renewable Energy

On Friday, July 8th at the Potomac Watershed Roundtable meeting Thomas Smith, Solid Waste Division Chief of the Prince William County Public Works Department gave a presentation on Utilizing the Landfill Gas for Renewable Energy Production followed by a tour of the Prince William Landfill.

Prince William County residents pay a flat fee ($70) every year on their property taxes so there is no tippage fee at the landfill. This fixed fee that grows with population allows the landfill to have a steady cash flow to maintain their monitoring and remediation programs and plan smooth expansion and improvement programs. Trash generation in general grows with population, but it is surprisingly subject to the economy. The population of Prince William County was 281,287 in 2000 and grew more than 43% to 402,002 in 2010. In 2000 238 thousand tons of trash was disposed at the PW Landfill. The peak tons of trash disposed the PW Landfill was 367 thousand tons in 2007 in 2010 285 thousand tons of trash were disposed at the landfill. To put that in perspective, in 2007 it was estimated that Prince William Residents generated about 6 lbs of trash per day per person; today that number is less than 4 lbs of trash per day per person. Approximately, 32% of the trash is recycled, 10% is recovered as energy, and 58% is buried in the landfill. According to Mr. Smith much of the trash going to the landfill could have been recycled, but recycling and the recycling center at the landfill is a topic for another day.

Prince William Landfill is right off of Dumfries Road in Manassas, VA and has operated at this location since 1972. The oldest section of the landfill contained 57 acres that were closed in 1991 when the state law known as HB 1205 went into effect. That area is currently used for little league fields and have been undergoing retrofit with liners and leachate and landfill gas collection systems to protect the environment. Today Prince William County Landfill is engineered and built as a series of cells. The cells include liners of plastic membranes and watertight geosynthetic clay liner fabric on the bottom along with a leachate collection system. At the end of each day, earth covers the trash deposited in the cell, to keep animals away and improve aesthetics. When a cell if full it is capped to prevent (or at least limit) the rain that percolates through the landfill and covered in soil. Currently, the landfill is capping the Phase I section and opening up a newly lined cell in the Phase II area.

The PW Landfill has 48 groundwater monitoring wells that are observed and/or sampled quarterly to ensure that groundwater is not impacted or any impact is contained and 78 landfill gas extraction wells. Landfill gas is generated during the natural process of bacterial decomposition of organic material contained in the trash buried in the landfill. Landfill gas is approximately forty to sixty percent methane, with the remainder being mostly carbon dioxide. Landfill gas also contains varying amounts of nitrogen, oxygen, water vapor, sulfur, and other contaminants. The gases produced within the landfill are either collected and flared off or used to produce heat and electricity. The landfill gas cannot be allowed to build up in the landfill because of the explosive potential. PW Landfill has operated for almost 40 years and has more than 7 million tons of trash buried at the landfill. That trash currently generates 2,700 standard cubic feet per minute of landfill gas up from 1,600 scf/m in 1999.

Landfill gas can be used as a source of energy to create electricity or heat. It is classified as a medium-Btu gas with a heating value of 350 to 600 Btu per cubic foot, approximately half that of natural gas, and can be used in place of propane and natural gas in some application. It is a reliable source of energy because it is generated 24 hours a day, 7 days a week. Landfill gas is a renewable energy source. Landfill gas that is used to produce energy does not have to be flared and wasted to prevent explosive gas build up. Flaring of landfill gas at PW landfill is done in a candle flare an open air flame that you have probably seen at night. In 1998 the County formed a partnership with NEO Prince William to install a landfill gas collection system and a 1.9 MW energy recover facility which is a two engine turbine that burns the gas to make electricity that is sold to NOVEC, the local electric cooperative. The 1.9 MW energy recovery system was utilizing less than 25% of the currently available landfill gas for energy recovery.

NEO was acquired by Fortistar Methane Group. Fortistar has since obtained the VDEQ permits for four additional engine turbines. Negotiations with NOVEC were more difficult because Virginia has no renewable energy requirements, but 3 MW of additional engines will go on line this year for a total constant energy production of 5 MW. This will produce $40,000 annual revenue to the Solid Waste Fund and $20,000 in personal property tax revenue in the first year. Even after the new engines go online this year there will still be 200 scf/m excess landfill gas available. A new gas pipeline has been installed to provide landfill gas to heat the landfill’s Fleet Maintenance Building and extended to provide fuel to the County animal shelter cremation incinerator to replace propane. The payback for the pipeline installation is estimated to be 8-10 years. Propane use will be reduced 56% and the savings to the general fund will be $25,000-$35,000 annually.

As the landfill continues to operate, adding closed cells and opening new cells, more landfill gas will be produced for generations. Prince William County views the landfill as an under utilized resource and is studying options for creating a Prince William Renewable Energy Park. The PW Landfill has applied to EPA for technical assistance in performing feasibility studies for the potential options.

Methane and Global Warming

During the Copenhagen meeting almost unnoticed Robert Watson, the former chair of the Intergovernmental Panel on Climate Change and Mohamed El-Ashry, a senior fellow at the United Nations Foundation along with a group from the scientific and financial communities proposed the creation of a Global Methane Fund. According to this group, targeting methane reduction would be a cost effective and results oriented way to prevent global warming. Methane, one of the "other greenhouse gases," is reportedly responsible for 75% as much warming as carbon dioxide measured over any given 20 years. Unlike carbon dioxide, which remains in the atmosphere for hundreds of years, methane lasts only a decade so reductions in methane release will see climate results within a decade as the total methane in the atmosphere is reduced. According to NOAA, National Oceanic and Atmospheric Administrations, CH4 which absorbs 25 times the heat of CO2 is present in the atmosphere at 1/50 the level of CO2 at 1.8 ppm. Methane levels in the atmosphere have risen for the first time since 1998. This increase was attributed to changes in the permafrost stores of methane.

According to this group if we need to suppress temperature quickly in order to preserve glaciers, reducing methane can make an immediate impact. Compared to the massive requirements necessary to reduce CO2, cutting methane requires only modest investment. This group argues that where they stop methane emissions, cooling follows within a decade, not centuries. Methane amelioration would require non-point source regulation and activity. Methane (CH4) is emitted from a variety of both human-related and natural sources. Methane comes from a variety of sources: landfills, sewage streams, coal mines, oil and gas drilling operations, agricultural wastes, and cattle farms. In the United States, the largest methane emissions come from the decomposition of wastes in landfills, enteric fermentation in ruminant digestion and manure management associated with domestic livestock, natural gas and oil systems, and coal mining. Enteric fermentation occurs when methane (CH4) is produced in the rumen as microbial fermentation takes place. Most of the CH4 byproduct is belched by the animal; however, a small percentage of CH4 is also produced in the large intestine and passed out as gas.

According to the US EPA the largest emitters of Methane in the United States in 2007 was enteric fermentation. I kid you not, belching and (please excuse me) farting animals.

U.S. Methane Emissions by Source (TgCO2 Equivalents)

Source Category 2007
Enteric Fermentation 139.0
Landfills 132.9
Natural Gas Systems 104.7
Coal Mining 57.6
Manure Management 44.0

The Global Methane Fund, does not address the release of methane from the permafrost. In an Opinion piece in the Wall Street Journal Mr. Watson and Mr. Mohamed El-Ashry state “experience has shown that even with modest incentives, methane projects, which are typically small scale, can move fast.” These two gentlemen suggest the creation of a global fund. It won’t work. Methane results from human, animal and plant waste. Landfills are prodigious methane generators and because they are a point source can easily be harvested to produce biogas electricity. The release of methane from the permafrost is not even considered. Though the model for causation is not worked out nor proven, it is argued that un-combusted methane released into the atmosphere is a powerful greenhouse gas and 10% of our nation's impact on the climate comes from the food refuse that ends up decomposing under landfill, and another 10% comes from the gaseous releases of enteric fermentation.

In a New York Times article by Leslie Kaufman, “Greening the Herds: A New Diet to Cap Gas.” Cow that had their grain feed adjusted to include more plants like alfalfa and flaxseed and less corn produce less methane. This feed is more like the natural grasses that the cows evolved eating. The methane output dropped 18-30% depending on the original feed mix while milk production remained stable. In addition to producing less methane, the cows were observed to be healthier. This study evolved out of research performed by the makers of Danon yogurt in France. Scientists working with Groupe Danone had been studying why their cows were healthier and produced more milk in the spring. The answer, the scientists determined, was that spring grasses are high in Omega-3 fatty acids, which may help the cow’s digestive tract operate smoothly.
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Corn and soy, the feed that became dominant feed in the agro-industrial dairy industry, has a completely different type of fatty acid structure. As was carefully chronicled in Michael Pollan’s book “The Omnivore’s Dilemma” during the past 40 years, our agricultural economy as orchestrated by the Department of Agriculture has created a system of fattening cows using an unnatural feed, corn and soy. Cows are healthier and belch less methane if they are feed a diet similar to one they evolved to eat. This should not be surprising and is a small example of unintended consequences of man trying to bend the earth to our will. Our tools to impact and change remain far more powerful than our wisdom to know the right course of action to take with them. We would be far better off if we could restrain ourselves from wide sweeping actions and $100 billion global investment funds and dip our toes in first to see the results. Try to develop wisdom before we try to manage the natural cycles of the earth, and instead follow the earth’s lead. Concentrate our global funds on teaching sustainable farming, sanitation, and providing fresh water .

Cows, Methane Gas and Climate Change

The consensus of scientists believe that human activities are changing the composition of the atmosphere, and that increasing the concentration of greenhouse gases will change the planet's climate. However, they are not sure by how much it will change, at what rate it will change, or what the exact effects will be. Currently carbon dioxide is thought to be the critical greenhouse gas. According to NOAA, National Oceanic and Atmospheric Administrations, CH4 which absorbs 25 times the heat of CO2 is present in the atmosphere at 1/50 the level of CO2 at 1.8 ppm. Methane levels in the atmosphere have risen for the first time since 1998. This increase was attributed to changes in the permafrost stores of methane. (According to NOAA, CO2 is present at 386 ppm.)

Lately, there seems to be a focus by environmental groups and nutrition activists on increasing meat consumption as the cause of the increase in methane and greenhouse gasses. The Center for Science in the Public Interest, Nutrition Action Newsletter points out that the consumption of animal products increases global warming due to a variety of causes and argues for the vegetarian life. CH4 is produced as part of normal digestive processes in animals. During digestion, microbes present in an animal’s digestive system ferment food consumed by the animal. This microbial fermentation process, referred to as enteric fermentation, produces CH4 as a byproduct, which can be exhaled or eructated by the animal. The amount of CH4 produced and emitted by an individual animal depends primarily upon the animal's digestive system, and the amount and type of feed it consumes. Ruminant animals including cows are the major emitters of CH4 because of their unique digestive system. Ruminants possess a rumen, or large "fore-stomach," in which microbial fermentation breaks down the feed they consume into products that can be absorbed and metabolized. The microbial fermentation that occurs in the rumen enables them to digest coarse plant material that non-ruminant animals can not. Ruminant animals, consequently, have the highest CH4 emissions among all animal types. In addition to the type of digestive system, an animal’s feed quality and feed intake also affects CH4 emissions.


On Friday in the New York Times was an article by Leslie Kaufman, “Greening the Herds: A New Diet to Cap Gas.” For the past five months cows at 15 farms across Vermont have had their grain feed adjusted to include more plants like alfalfa and flaxseed and less corn. This feed is more like the natural grasses that the cows evolved eating. The methane output of the Vermont cows dropped 18 percent while milk production remained stable. In addition to producing less methane, the cows were observed to be healthier. This study evolved out of research performed by the makers of Danon yogurt in France. Scientists working with Groupe Danone had been studying why their cows were healthier and produced more milk in the spring. The answer, the scientists determined, was that spring grasses are high in Omega-3 fatty acids, which may help the cow’s digestive tract operate smoothly.

Corn and soy, the feed that became dominant feed in the agro-industrial dairy industry, has a completely different type of fatty acid structure. The French sturdy found a reduction in methane release of about 30% at 600 farms. The difference from the Vermont experience was attributed to the fact that the Vermont animals were pastured and received some of their food from grasses. As was carefully chronicled in Michael Pollan’s book “The Omnivore’s Dilemma” during the past 40 years, our agricultural economy as orchestrated by the Department of Agriculture has created a system of fattening cows using an unnatural feed, corn and soy. Cows are healthier and belch less methane if they are feed a diet similar to one they evolved to eat. This should not be surprising and is a small example of unintended consequences of man trying to bend the earth to our will. Our tools to impact and change remain far more powerful than our wisdom to know the right course of action to take with them. We would be far better off if we could restrain ourselves from wide sweeping actions and dip our toes in first to see the results. Try to develop wisdom before we try to manage the natural cycles of the earth, and instead follow the earth’s lead.