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Modern Well Development Technology Produces Big Time Environmental Benefits for Michigan

Technology used to develop natural gas resources has taken giant leaps forward in recent years providing huge benefits to  Michigan’s environment. These improvements have enabled the state to develops its energy resources to the benefit of Michigan’s consumers and economy while protecting the landscape that makes the Wolverine State unique.  While the promise may sound too good to be true, the facts incontrovertibly support this conclusion.  The combination of horizontal well boring and hydraulic fracturing has reduced the footprint of modern natural gas development on the land, while also allowing our nation to achieve dramatic reductions of greenhouse gases thought unthinkable just a few years ago.

Natural gas development in Michigan was, until recently, was conducted with vertical wells which housed only one well per well pad.  Historically, vertical wells depended on the ability to target particular reservoirs of gas or hit natural fractures in the shale that would permit recovery of gas from an area of 20-40 acres on average, although 20 acre units are no longer practical.  Today, natural gas is being developed using directional and horizontal drilling technology that allows multiple wells to be drilled from a single well pad.

Horizontal wells have the advantage of magnifying the portion of a formation that can be tapped from a single well, simultaneously increasing production and reducing the footprint of development on the surface.  New development units are now, typically, a minimum of 160 acre. Assuming 160 acre units for multi-well horizontal well development, this would require 4 horizontal wells on a single pad to develop 640 acres.  This same 640 acre development would require 16 vertical wells and 16 pads assuming 40 acres units using vertical drilling technology.  This means what required 16 well pads with vertical wells now requires one well pad with horizontal wells.  Unit sizes are trending toward two square miles in some areas of the country, which means one horizontal well pad potentially replaces 32 vertical well pads.

Whether one is measuring initial land disturbance (typically in the neighborhood of 4-5 acres per pad for a vertical well) or final pad size (1-2 acres), the difference is huge.  Vertical well development of a square mile can require disturbing as much as 80-100 acres of land over time with access roads, while horizontal development may require as little as 5-10 acres even adding in the access road required.  It’s hard to imagine an economic activity with so much energy and income generation potential and so little land impacts.

Maps maintained on the Michigan Department of Environmental Quality website provide plenty of examples of older smaller units developed with vertical wells compared to new 160 acre units where horizontal drilling technology has been used. The below illustration provides a good comparison. A 4-well horizontal well pad will require 8 acres and a horizontal well pad with 6+ wells will require 8.5 acres.  Notice how disturbance is dramatically reduced by horizontal well development to the point that as little as 0.7% of the land is initially disturbed in larger units (not including access roads and the like) and this gets reduced even further upon completion of development.

Still another perspective is offered by the below illustration which depicts the development of a two square mile unit using 40 acre units (left) and a 1,280 acre unit (right), which is where the industry is headed long-term.  There have already been proposals to develop units of this size in Michigan.

A unit of 1,280 acres in size with one well pad of 8.5 acres, 5 acres of access road and another 5 acres for fresh water storage would disturb a total of 18.5 acres at the outset.  That is 1.4% of the land area involved and when the wells are all completed the impervious surface is likely to be closer to 0.5%.  Residential, commercial, industrial and, even agricultural uses, all require far more land disturbance.  Moreover, the income from natural gas royalties enables landowners to maintain farms, forests and open spaces.  A report from the Michigan Department of Natural Resources, in fact, identifies the “increased tax burden on private individuals holding forestland, thereby creating incentives to sell such land for residential development,” as a major threat to Michigan forests.  Natural gas development is one of the answers to that threat, allowing forests to generate economic rent with minimal forest disturbance.

Not only does natural gas development contribute to maintaining open space, but it is, also, helping the U.S. near Kyoto targets for greenhouse gas reductions without even being a party to the treaty, far surpassing Western Europe and other nations who did sign onto the treaty.  My associates here at Energy In Depth earlier reported that, according to the International Energy Agency (IEA), the increased use of natural gas in the United States may be the single largest factor in America’s greenhouse gas (GHG) reductions.  They noted the International Business Times Green Economy reports:

 “{GHG} emissions in the US and EU dropped, 1.7% and 1.9% respectively. The warm winter helped, and the sluggish economy was certainly a factor, but the biggest change was the drop in coal use in favor of natural gas.

“The replacement of coal by shale gas is a key factor and what happened in the U.S. could very well happen in China and other countries and could definitely help in reducing CO2 emissions,” says International Energy Agency (IEA) chief economist Fatih Birol.”

Carbon emissions have dropped in four of the last six years and are currently at their lowest point in the last 20 years. The main reason for this achievement is the increasing use of natural gas in U.S. power systems made available by hydraulic fracturing.  Here is what the Energy Information Administration says about the subject:

In 2011, GDP grew by 1.8 percent, but emissions decreased by 2.4 percent (136 million metric tons).  This indicates that the carbon intensity of the economy declined by about 4.2 percent.  The 2011 decrease is only the fourth year since 1990 to experience a decline in carbon intensity of greater than 3.5 percent for the economy as a whole and only the sixth year since 1990 to experience an emissions decline.  Since 1990, energy-related carbon dioxide emissions in the United States have grown much more slowly than GDP – in 2007 emissions were 19 percent greater than their 1990 level, but by 2011 were only about 9 percent above the 1990 level.  GDP has increased by 66 percent over that same time period. (emphasis added)

The EIA also, in comparing energy consumption to CO2 emissions by energy source, reports “Natural gas, on the other hand, provides 26 percent of the energy consumed but 24 percent of the emissions.”  This means every switch from other carbon sources to natural gas results in a net reduction in carbon emissions.  And, how is that natural gas produced today?  Well, with a combination of horizontal drilling and hydraulic fracturing which are now involved with up to 90% of all new natural gas production.

According to IEA data, U.S. carbon emissions have fallen by 430 megatons (7.7 percent) since 2006. This drop is equal to eliminating the combined emissions of ten western states: Alaska, Washington, Oregon, Idaho, Montana, North Dakota, South Dakota, Wyoming, Utah and Nevada.  That’s huge – huge enough to produce a headline saying “USA leads world in CO2 cuts since 2006” and the following chart:

 

What makes this success even more compelling is that just eight years ago many criticized our nation for not ratifying the Kyoto Protocol. This criticism only grew when Congress failed to enact a cap and trade policy that sought to reduce carbon emissions via government regulation.  Yet, here we are approaching the targets and leading everyone else in doing so.  This is, in fact, what the IEA says:

CO2 emissions in the United States in 2011 fell by 92 Mt, or 1.7%, primarily due to ongoing switching from coal to natural gas in power generation and an exceptionally mild winter, which reduced the demand for space heating. US emissions have now fallen by 430 Mt (7.7%) since 2006, the largest reduction of all countries or regions.

It doesn’t get better than this.  Natural gas is reducing footprints everywhere on the earth and in the skies.

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