Al Saving Energy

Thursday, February 2, 2012

Hydraulic Fracturing/Fracking, Pros & Cons

PRO HYDRAULIC FRACTURING

Potential Energy Independence: Fossil fuels extracted domestically can help wean us off of our addiction to foreign oil.

Clean and Economical Fuel: Replacing coal powered plants with natural gas plants and gasoline engines with natural-gas-powered ones could work as part of a plan to reduce greenhouse emissions significantly. Natural gas is also proving to be a cheap source of energy.

Local Economic Benefits: Extraction of fossil fuels is already a major source of employment in the U.S. Increased drilling will lead to more jobs. In addition,leases and royalties put money into economically-depressed areas.

Buys Time To Develop Renewable Energy : Natural Gas can serve as a bridge fuel to a 21st century energy economy that relies on efficiency, renewable sources, and low-carbon fossil fuels.

CON FRACKING

Severe Water and Air Pollution: Extracting natural gas by fracking leads to major pollution of wells. This has caused numerous cases of severe health problems for both humans and animals.

Fracking Has Led To Earthquakes: Several earthquakes, including eleven in Youngstown, have been linked either to the hydraulic fracturing process or to wells for disposal of spent fracking fluids.

Requires Large Amounts Of Water: The fracking process can require around large amounts of water. Fracking is exempt from the Safe Drinking Water Act of 2005, thus allowing companies to conceal the chemicals used in the process. Concerns about these chemicals include carcinogens and radioactive waste.

Large Clean-up Costs : Drilling leaves behind damaged roads, damaged land, and an unsafe environment. Real estate values plummet.

Wednesday, January 11, 2012

Non-Intuitive Result

This quote was in response to a query from Adrian Demaid (Open University, UK), who asked me for examples where research had an unexpected result.

“About twenty-five years ago Battelle was asked to estimate the cost of fracture to the US economy, we came up with an amount of about a few percent of gross domestic product. While the actual figure can easily be disputed, the real cost is probably very large.

The key to arriving at our result was an appreciation of the role that material variability plays in engineering specifications. It appears that typical engineering standards assign properties about two standard deviations below the mean of alloys when specifying dimensions. For example, if the coefficient of variation of the yield strength of a particular steel is seven percent, it is assumed that all pieces of that steel are treated as if their yield strength is 14 percent below the actual mean. Of course, engineers did not work this position out statistically -— the various rules-of-thumb just seem to come out that way. If metallurgists could reduce scatter consistently, we would have lighter structures with no sacrifice of safety. Extending this idea to other mechanical properties and plugging our estimates into the economics model gave rise to the large costs that we reported.

The above argument leads to the non-intuitive conclusion that the fracture research with the greatest economic benefit would be in the area of materials production (especially welding). Our report soft-pedaled this point, since the sponsors had a vested interest in justifying additional funding for fracture mechanics research.

When I made my point about the importance of production research, at technical meetings, I was attacked by researchers with the same motivation — they cited all sorts of unsolved analytical problems and promising experimental approaches. My reply that success in their approaches would at best lead to a tiny reduction in safety factors only poured oil on the fire.”

Monday, January 2, 2012

Fracking Can Cause Earthquakes (Rev. 7 Jan 2012)

Scientists have coined the term 'induced seismicity' to describe earthquakes caused by human activity. Several examples of earthquakes in the past caused by oil and gas drilling have been documented. These earthquakes can be triggered when water under pressure encounters a fault (i.e., a crack in the subsurface rock, which can be very small or up to miles in extent)*

The fracking process produces tiny earthquakes as a side effect of the cracking to release the gas. and oil trapped in the rock. But they are detectable only by sensitive instruments. The question is whether the current technology being used in Ohio can trigger earthquakes large enough to be felt by humans. In order to avoid the possibility of earthquakes, the driller has to be sure that his shaft does not encounter a fault. Unfortunately, the the number, size, and location of all faults in Ohio is unknown.

In the first half of 2011, people living in both England and Oklahoma felt tremors. In both places expert analysis has suggested that they were caused by fracking. The second half of 2011 has seen major earthquakes centered in both Virginia and Oklahoma. Activists have claimed that these bigger earthquakes are also caused by fracking, but a good case has not yet been made.

There is also evidence of earthquakes at, or near, fracking-waste-water injection well sites (storage pits). Good evidence for such earthquakes was found near injection wells in Arkansas; there were multiple small earthquakes, whose numbers and intensity greatly diminished when injecting liquid into the wells was stopped. Other suspect earthquakes have recently occurred in Texas and West Virginia, as well as in Ohio (Youngstown and Marietta).

It is not only fracking waste that can cause earthquakes – any liquid will do. In an on-line comment on a 31 December, 2011 article in the Columbus Dispatch, Jeff Cox wrote:

“The increase of fluid pressure from the injection of liquids wastes in northeast Ohio and near Lake Erie by the Stauffer Chemical Company into a nearly 6,000 feet deep sandstone formation was implicated by Ohio University researchers to have triggered a 5.0 magnitude earthquake and two aftershocks on January 31, 1986 … Two and possibly three prior earthquakes in that area during 1983 are thought by researchers to have likely also been caused by the same deep well injection site. ... The Ohio Geological Survey and other geologists determined that a sequence of earthquakes of magnitudes ranging from 2.6 to 4.3 that shook downtown Ashtabula, Ohio from 1987 to 2003 were caused by a nearby deep well site injecting hazardous waste fluids near two faults into a 5,900 feet deep basal sandstone formation. The researchers state, “like many faults that rupture in … stable subcontinental region earthquakes, the faults were previously unknown…”

Youngstown suffered eleven earthquakes in 2011. After the magnitude 4.0 quake on New Year's Eve, the State finally stepped in and ordered a five-mile exclusion zone around the guilty injection well and verified that a previously unknown fault the cause. Subsequently the owner of the well agreed to empty it.

Some have argued that there are very many injection wells that do not cause earthquakes. This is true. It is only the unlucky driller who encounters a fault and triggers an earthquake. At a minimum, Ohio should forbid deep drilling at locations near critical infrastructure (bridges, dams, pipelines, etc.) and in areas of high population density.

The West Virginia State Geologist, faced with a Youngstown-type situation, has called for a mapping of faults. This is good advice for Ohio, since we don't know where all of the faults in the State are located.

ADDED COMMENTS

9 Jan 2012:Article in Columbus Dispatch: State to buy seismomiter (sp ?)

10 Jan, 2012: Letter to the Columbus Dispatch from API executive "The overwhelming majority of hydraulic-fracturing operations take place without any reported seismic activity" meaning that they concede that fracking can cause earthquakes.

11 Jan 2012: CAVEATS:

1. Solving the earthquake problem does not mean that I am giving deep drilling a green light. The very serious pollution-generation and explosion-potential problems remain.

2. By far the greatest sources of energy waste and greenhouse-gas generation are electric power plants and motor vehicles. The technology exists to replace coal and gasoline with natural gas. The industry has an obligation to produce the gas with the greatest regard to publichealth and safety.

14 Jan 2012: Found reports of induction-well-caused earthquakes in local papers from NY ("Fracking Sparks Eartquake Concerns ", democratandchronicle.com, 16 N ov. 2011) & SC

15 Jan 2012: Report found from Reuters that sensing out faults will cost $5 million per well. But I believe that the Governemnt is doing a nation-wide survey which is due in Ohio in two years.

Friday, December 23, 2011

Evidence against fracking enough to be concerned

(This is the letter that I published in the Marietta Times on 28 Dec 2011. For a more complete update, including further reading, see this blog for 2 Jan 2012)

While researching a possible link between fracking and earthquakes, I found that The Times doubts that such a link exists. In fact, the opposite is true - a link is very likely.

The fracking process produces tiny earthquakes as a side effect of the cracking to release the gas. And oil trapped in the rock. But they are detectable only by sensitive instruments. The question is whether the current technology being used in Ohio can trigger earthquakes large enough to be felt by humans. In order to avoid the possibility of earthquakes, the driller has to be sure that his shaft does not encounter a fault. Unfortunately, the number, size, and location of all faults in Ohio is unknown.

There is also evidence of earthquakes at, or near, fracking-waste-water injection well sites (storage pits). Good evidence for such earthquakes was found near injection wells in Arkansas; there were multiple small earthquakes, whose numbers greatly diminished when injecting liquid into the wells was stopped. Earthquakes near injection wells close to Youngstown in 2011 may have had the same cause. Other suspect earthquakes in 2011 occurred in Marietta and in West Virginia.

All of the events mentioned above happened in 2011. Scientists have been aware of fracking-induced earthquakes for some time, but the public is just starting to become aware of the connection. While the evidence may not be solid enough for a court of law, there is enough evidence for serious concern.

Several organizations, including the League of Women Voters of Ohio, have called for a moratorium on drilling. Clearly a pause is needed until the geological faults in Ohio have been mapped. Otherwise a deep hole will be drilled into an earthquake fault and filled with water - actions that can trigger an earthquake.

Documentation of the facts in this note can be found on my blog for 23 December 2011.

Alan R. Rosenfield, ScD FASM

Columbus

Friday, December 2, 2011

Ohio Electricity Goals

Starting in 2009 Ohio law has mandated that investor-owned electric utilities meet specific annual goals for renewable electricity ( Ref. a). The PUCO web site reports the in-state renewable energy requirements for all years up to 2025 (b).This note provides information on how well we are meeting these requirements.

The Appendices provide background information. Appendix A is a primer on electricity terminology, while Appendix B provides the relations among the terms that I have used. Appendix C discusses the relative costs of various energy sources.

The non-solar goal for 2025 is 8.67 million MWh, requiring 2000 to 3300 MW capacity. Current thinking is that the bulk of Ohio's renewable electricity will be provided by wind and biomass. By the end of 2011 Ohio will have 400 MW of wind power (c). There also will be some electricity from biomass, although the amount is very uncertain. I have estimated two limits for biomass:

37 MW – only the power available using landfill gas (d)

251 MW – the total biomass renewable power approved by PUCO (e)

Using the mathematical relations from Table A-2 Ohio's current capacity can provide between 1.2 and 2.4 million MWh annually. Even if the lower limit is correct, Ohio already has about enough non-solar capacity to satisfy its 2013 goals.

The solar goal for 2025 is 361 thousand Mwh, requiring about 300 MW capacity

Ohio now has 28 MW of solar energy (f), which can produce about 34,300 Mwh of electricity annually. This amount is only 88 percent of the 2012 goal. However, there is reason to believe that this shortfall has been corrected (g).

References

a. ORC 4928.64, online at http://codes.ohio.gov/orc/49

b. http://www.puco.gov/ “Ohio Alternative Energy Portfolio Standard – Certified Renewable Energy Facilities (as of 11/01/11)

c. E. Thumma: Testimony before the Joint Public Utilities Committees of the Ohio
General Assembly (11/02/11)

d. www.puco.gov “where does Ohio's electricity come from?”

e. www.puco.gov “OHIO’S ALTERNATIVE ENERGY PORTFOLIO STANDARD - CERTIFIED RENEWABLE ENERGY FACILITIES”

f. Colin Marchie: Testimony before the Joint Public Utilities Committees of the Ohio
General Assembly (11/02/11)

g. First energy Press Release, 07 Nov. 2011

APPENDIX A - BACKGROUND

A-1. This is a section about basic electrical units for newbies. You are probably aware of two ways of measuring electricity: your monthly bill reports how much you have used in kilowatt-hours (kWh) and the number of watts (W) in a light bulb tells you how brightly it will shine.

When we write about the electricity that the whole state produces, we need to use bigger units. Power plants (whether coal, nuclear, or wind turbine) are rated in Megawatts (MW, where 1 MW = 1000 kilowatts [kW] and 1,000,000 watts [W]). It is important to understand that watts measure the rate of producing or consuming energy – 1 kilowatt means that a power plant can produce 1 kilowatt-hour of electricity every hour.

To find the amount of electricity produced by a generator or used by a piece of equipment, its watts (or kilowatts) need to be multiplied by the time that it is working: a 100 watt light bulb burning for four hours requires 400 watt-hours (or 0.4 kWh) of electricity.

While Watts measure rates of production or consumption, the units containing hours, such as kWh, measure the total amount produced or consumed. The same relations apply : 1,000 Wh = 1 kWh, 1,000 kWh = 1 MWh.

A-2. The capacity factor is an additional complication. It takes into account variability in operating time and power. Formally, the capacity factor is the ratio of how much electricity is produced to how much would be produced if a unit was running at full power all of the time. For example, a solar array could never run more than 50 percent of the time, because the sun only shines half of the time during the course of a year (actual capacity factors for solar arrays are much smaller because of cloud cover). Table A-1 reports the values of capacity factor that I have been using. Different technologies have different capacity factors and capacity factor may vary for different installations (a location with more frequent high winds will have a higher capacity factor than one less-well sited).

Table A-1. Typical values of capacity factor. (all values are from the U.S. Energy Information Administration [EIA] “Average Capacity Factor by Energy Source”, except as otherwise noted)

Nuclear = 0.92

Landfill Gas = 0.85, based on various sources

Coal = 0.74

Biomass, purpose-built plant = 0.7, based on Glatfelter PUCO data

Biomass, co-fired in coal plant = 0.5, based on PUCO Duke calculation

Hydro = 0.36

Wind = 0.30, based on Blue Creek and Timber Road web sites.

Solar PV = 0.14, Value used by DPL in PUCO submission

Ohio renewable average, according to EIA for 2007 (latest available) = 0.45

Replacing one type of generator with another results in a different amount of electricity (MWh) for the same power (MW). To get the same amount of electricity from each source, multiply the power by the ratio of capacity factors. For example for each MW of coal replaced, the wind requirement is the ratio of the coal capacity factor to the wind capacity factor = 0.74/0.30 or about 2.5. To replace a 500 MW coal Pant requires about 1250 MW of wind power.

A-3. This section concerns estimating annual electricity production form a power source. I used the mathematical relations in Appendix B for these estimates. Two values are reported: the output per megawatt is in parentheses ( ) and the number of households that can be powered by one megawatt. According to EIA, the typical Ohio home uses about 11,000 kWh annually.

Table A-2 – Annual Electricity Production from a Power Source per Megawatt of Capacity

Power Source	MWh per MW	Houses per MW
Nuclear	8060	735
Landfill Gas	7450	680
Coal	6480	590
Biomass*	5260	480
Hydro	3150	290
Wind	2630	240
Solar PV	1225	110

* Average values based on the two estimates in Table A-1 have been used.

As an example, a 2 MW wind turbine can supply enough electricity for almost 500 households.

Appendix B – Mathematical Relations

B-1: Calculation of Goals

The basic relation between capacity and energy is:

E = PCt = 8760PC ...(1)

where:

E = electrical output in MWh

P = source capacity in MW

C = capacity factor

t = time = 8760 hr/yr

To find the annual capacity required to meet Ohio's goals, we define two new terms:

E* = annual renewable consumption to be generated in Ohio in mWh

P* = Required capacity, depends on power source in MW

Rearranging Eq. (1)

P* = E*/Ct = E*/8760C ... (2)

Non-Solar

Because the non-solar goal will be met by using several technologies (c), the overall capacity factor is unknown. Taking limits of C of 0.3 and 0.5:

R* = 8.67 MWH

From Eq. (2): P* = 2000 to 3300 MW.

Solar Set-aside

R* = 361 thousand MWh

From Eq. (2): P* = 300 MW

B-2 Calculation of the number of Households Served

If H = The number of households that can be powered per MW of electricity varies with energy source:

PCt = eH ...(3)

Rearranging:

H/P = Ct/e = 800C ... (4)

where e = average household requirement = 11,000 kWh/yr. (EIA estimate for Ohio)

Monday, November 21, 2011

Frackquakes

I have done a bit of thinking about earthquakes and fracking.

As I understand it, the Blackpool earthquakes were a direct result of the fracking process. The surface of the well hole was exposed to liquid under high pressure.

In this country, earthquakes in Arkansas and Ohio happened near fracking-liquid disposal pits. Since these pits are extremely deep, there is a high hydrostatic pressure on the pit wall.

In both cases, if a hole is drilled that intersects a geological fault, there is the possibility that liquid will be forced into the fault. Under these conditions, the fault can be unlocked and lubricated by the liquid, particularly if it is a shear fault.

This idea is so simple, that I would be surprised if it hasn't been suggested before.

ADDED 19 Dec 2011 - It has been suggested; see Wikipedia

Monday, November 7, 2011

Renewables vs. Industry Electricity Cost

The data below show that there is no relation between the percent of renewables and the cost of electricity for industry.

State	Industrial Cost, cents/kWh (a)	Renewable Electricity, % (b)
Illinois	7.5 (10)	1.9
Indiana	5.74 (4)	1.9
Iowa	5.33 (2)	16.5
Kentucky	4.98 (1)	4.1
Michigan	7.2 (9)	3.9
Minnesota	6.3 (7)	14.4
Missouri	5.46 (3)	2.7
Ohio	6.06 (6)	0.9
West Virginia	5.78 (5)	3.4
Wisconsin	6.74 (8)	6.2

(a) electricchoice.com; numbers in parentheses rank from cheapest to most expensive

(b) US Energy Information Administration; State Renewable Energy Profiles; 2009 data (latest available)