Tech Talk - Geothermal Plant Opens

The Missouri University of Science & Technology Geothermal system was officially opened last Thursday, some months after the coal and wood fired power plant that had previously warmed the campus had been shut down.

Figure 1. Chancellor Schrader cutting the ribbon to officially open the system.

The operation ended up being a little larger than originally anticipated, although the receipt of several grants kept the need for external funding bonds down to $30 million. Overall, as the old heating and cooling system was replaced around campus, deferred maintenance costs of some $60 million disappeared as the new system eliminated those needs, and is anticipated to generate fuel overall savings of some $1 million initially rising to $2.8 million a year as future fuel prices rise over the years.

In the end some 645 wells were drilled to feed three different geothermal plants located around the campus. Well depths ranged from 420 to 440 ft., and with a background temperature around the wells averaging around 60 deg F.

The installed system is, to a large extent, computer controlled, so that it was necessary to find employment for the fifteen workers at the power plant who would otherwise have been laid off. Given that some took retirement, the University was able to absorb the rest into the workforce in various ways. But it does point out that, now that the system is installed, the number of jobs associated with this new sustainable energy system are significantly below that required at the power plant, and the coal mine and forestry products supplier that previously supplied the fuel. Maintenance of the system, which is largely built around pumps, pipes and valves can, in the main, be carried out by the normal trades staff at the campus.

Figure 2. Overview board for the individual geothermal flow loops

To illustrate the degree of control that the new system exerts on the Heating and Air Conditioning (HAC) network, consider a simplified circuit for one building.

Figure 3. Illustrated circuit for a single building

Hot water is fed into the building from the network (top left) at a temperature of 118.7 degF, and is mixed with a portion of the previously circulated fluid to give a starting temperature of 113.6 degF entering the building. (The values are in the small boxes over the sensing valve emulations). The hot water circulates around the building providing heat as needed. At the point where the water would exit back to the network for reheating the temperature of the returning water is measured (in this case 102.3 degF). Depending on that temperature a control valve opens or closes to send more (or less) water back for reheating, while the remainder stays in the circuit, with make-up from the main network. (with the valve 41.3% open some 3% of the returning water is being recycled). The computer also calculates the heating load being fed to the building (327.5 kBtu/hr).

Figure 4. Details of the control valve and instrumented values.

By using a similar circuit for cooling the components of the system are largely similar, reducing the inventory costs for maintenance supplies, and the two circuits are simply monitored through instrumentation around the circuit.

This is similarly true for the three geothermal plants, the status of each of which is also represented by a monitoring screen.

Figure 5. Control circuit monitoring the performance of the heat exchangers between the field circulation water and that being used in the building circuit.

The heat exchanges between the ground water and the heating/cooling circuits is through use of three screw type heat recovery chillers, the operation of which is described as:

A heat recovery chiller operates on the basis of a refrigeration cycle: the same basic cycle that is used for refrigerators, air conditioners, and heat pumps you find in your homes. It is designed to provide both useful cooling and useful heating energy from the machine. The work or energy put into the machine through the compressor is used to simply transfer heat from evaporator to the condenser, which makes it a more efficient use of energy than combusting fuel for heat.

As seen in the diagram below, the refrigerate, R-134a in our chiller, is first compressed using a screw-type compressor. This hot gas is then condensed to a liquid as it travels in a circuit through the condenser, and heat is transferred to the water flowing through the condenser tube bundle. The pressure and temperature of the refrigerant is reduced as it flows through the throttling valve. The refrigerant next passes through the evaporator where heat is transferred from the water flowing through the evaporator tube bundle back to the refrigerant. Then the cycle repeats as the refrigerant goes back to the compressor. The refrigerant is confined inside of the heat pump chiller for the entire process.

Figure 6. Operation of the heat exchanger.

Figure 7. Overview of the three chiller units in the McNutt plant

Manually readable gages provide back-up to the computer monitoring instruments.

Figure 8. Monitoring gages for the chilled water loop.

When additional heat is needed, this is provided by a bank of natural gas heaters for the water that can be engaged as needed, and that are similarly monitored.

Figure 9. Overall monitoring board for the natural gas boiler system

While the system may get an early test of effectiveness this week as a Polar Vortex brings an early taste of winter to town, with temperatures predicted to drop to a high of 34 and a low of 19 on Thursday.

Figure 10. Natural gas boiler to provide additional heat as needed.

Since I won't be able to take advantage of those boilers, I’m glad I have my wood stacked, and that I swept my chimney this morning.

Tech Talk - Closing a coal-fired power plant

Much is made of large schemes to alter the way in which energy is produced in the United States. Large scale wind farms, and great arrays of solar panels attract large interest and funding, yet it is often in the smaller projects, from the individual solar panels to the change in energy sources for individual factories, or in this case a university, that there is at least as much progress, though with less fanfare.

I wrote, some eighteen months ago about the geothermal plans at Missouri University of Science and Technology (MS&T) previously the University of Missouri-Rolla and my academic home for 42 years. At that time the campus was beginning a process that would see the different parking lots and other open areas around campus disrupted while a series of vertical wells and horizontal pipes was laid beneath the ground, prior to its restoration.

Figure 1. The MS&T Geothermal plan, showing the zoning of the wells and the connection pipe network.

Time has moved on since the initial plans were set in place, the trenches have been dug:

Figure 2. Geothermal trenches on campus, with walkways re-routed around them

Within the lots wells were then drilled roughly 430 ft deep, through which the system fluid will flow, and as these were drilled they were lined and connected by a secondary network.

Figure 3. Drilling the wells in the parking lots at the top right of Figure 1.

The network of wells is connected through plastic pipes that carry the water out to the wells, down and back up and then return to the central heat exchanger systems of the different circuits.

Figure 4. The heat exchange between the water and the ground (inhabitant )

Figure 5. The initial connections to the wells

Larger pipes are required to carry the water to and from the different fields to the processing plants where it is used to heat/chill water in a secondary circuit that is then distributed (depending on season to either warm or cool) through the network to the campus buildings.

Figure 6. The main pipe connections.

The parking lots have since been regraded, tarmac applied, and have, for some time been functioning as before.

Now the project is entering into the final days of installation, as a significant milestone has been reached. This week the coal and wood fired boiler #5 will shut down and all steam production at the campus power plant will permanently cease. Chillers are now operating for the summer to cool the buildings served by three of the regional plantsm which covers most of the air conditioning needs of the campus, and heat is being sent to six of the campus buildings.

Given the age, and change in the nature of the heating and air conditioning service to the buildings some still remain to have their systems upgraded, but most will now be completed while the students are away this summer.

Estimates of the savings that this will bring to the campus are in various forms. The coal and wood that have provided the energy source in the past will no longer be needed (and in time the plant will be removed). As well as the plant itself this will also free up the space where the coal was stored, and will improve the local aesthetic considerably along that side of the campus.

Figure 7. The campus power plant

The change in fuel will also see the overall amount of fuel required reduced, and it is anticipated that the energy use will be cut by 50%. Carbon dioxide emissions will be dropped by 25,000 tons a year (the system will still use significant amounts of natural gas) and water use will be cut by eight million gallons a year.

It is anticipated that the $32 million project will initially yield the campus a saving of around $1 million a year which will rise to more than $3 million a year as energy costs increase, while the system should not need significant maintenance for decades. There is a video of the project here). When completed, sometime next year the system will be serving 15 buildings with around a million square feet of floor space.

As the Missouri system was beginning, the initial phase of a similar system at Ball State was being completed . This will ultimately supply around 5.5 million square feet of campus space, and is expected to yield some $2 million a year in energy cost savings. Following the successful completion of Phase 1 of that project in March 2012, the Phase 2 project, requiring an additional 1,000 boreholes, was started in June of 2013, and is expected to be completed by some time next year. The four coal fired boilers at the plant (which consumed some 36,000 tons of coal a year,) were shut down in March of this year. Power will continue to be supplied from three natural gas boilers on campus. The $80 million project will have drilled a total of around 3,600 wells at the time of completion of Phase 2.

Oregon Tech has a 1.75 MW geothermal power plant, which combined with a solar electric array of panels on a 9-acre site off campus to produce most of the power needs of the campus. The dedication ceremony was on April 18th of this year. It is expected that the plant, which operates on a more conventional use of high-temperature water from the underlying host rock, will save the campus around $400,000 a year in energy. Water is brought up from 5,300 ft below the surface at a temperature of 200 degrees F, and used to spin two turbines, and as source of building heat, before being re-injected.

As the dates suggest this is a very new venture for universities and, as yet, there are not a lot of players in the game. Yet if the savings pan out to be at the level or greater than currently estimated it may well be more popular in the future as overall energy costs continue to rise. (Although in the short term natural gas prices may well rise a little, while coal prices are expected to fall a little).

OGPSS - More on the MS&T Geothermal Project

Ah, the election is over! Those outside the United States might not understand the relief, but as a minor example we had 6 different phone calls urging us to support Todd Akin for the Senate, in the 24-hours before our polling station closed. I am not sure that there will be much in the way of new information on Energy Policies out of Washington for a while, as they debate the fiscal cliff, but one does wonder whether we might get a new Secretary of Energy. And so, with Iranian oil production very much a function of how effective sanctions remain, and with the new OPEC Monthly Oil Market Report due, I am going to return for a second week to discuss the geothermal operations at MS&T, with a little more detail than last time, since some of the numbers might be of interest. (And I am grateful to Jim Packard at MS&T for providing the information).

Universities move generally very slowly. However they are, on occasion, willing to accept new ideas that resolve a problem quite quickly. (We once had to build a small plant to recover explosive and repackage it – not something that was possible on the surface, but by driving a new set of tunnels underground at the Experimental Mine we could create space for the plant and then operate it for the required demonstration without needing any of the permissions that would have been required had we tried to build a facility on the surface. (This was about 20-years ago, and we would likely still be moving the paperwork seeking permission). (Perhaps another argument for the accelerated use of underground space).

The case for a change in thinking, and, perhaps, a hint of its urgency, can be seen by looking at the energy balance, before the new system is installed.

Figure 1. Comparison of the useful energy (upper circled numbers) to the input energy at the MST Power Plant. (MST)

Given that fuel costs will likely only continue to rise, but that, while a new boiler was needed, there was no obvious source of funds to pay for it, a number of options were considered. It is interesting to note, in the following table, the costs of the current coal:wood system. (60% coal), relative to those of the proposed water to water (WTW) heat pumps that are being proposed.

Figure 2. Comparative Energy costs relative to the current system. (MST)

To digress a little, for their part in addressing a similar problem, the University of Missouri at the Columbia campus is installing a bubbling fluidized bed boiler. The boiler will use biomass to be to displace about 25% of the coal use on campus. The $75 million project has just been completed. However, as I noted in an earlier post, there may be unrecognized processing costs for the biomass which may eat into the campus savings. And while MS&T are looking for ways of handling the now unnecessary smoke stacks, the biomass facility in Columbia has just added three 110-ft tall silos to handle the feed.

The new boiler, which was retrofitted to the university’s existing heating duct system, is expected to produce 150,000 pounds of steam per hour, increasing the 67-year-old power plant’s steam output by 30,000 pounds per hour, and use an estimated 100,000 tons of in-state renewable energy sources such as chipped hardwoods and wood waste.

Back at MS&T the number for the heat pump came in part from a WTW heat recovery chiller that the campus had installed in October 2007, and which was saving the campus some $1,500 a day by allowing some of the recovered heat to be produced in useful form.

When the campus first looked at the potential they were also able to look at the experience of places such as the Richard Stockton College of New Jersey, which installed a system in 1996. Their installation pioneered many of the decisions made in subsequent operations.

The wells are located on a grid and spaced roughly 15 feet apart. Within each four inch borehole, the installers placed two 1.25 inch diameter high density polyethylene pipes with a U-shaped coupling at the bottom.

After the pipes were installed, the boreholes were backfilled with clay slurry to seal them and to enhance heat exchange. In total, the loop system includes 64 miles of heat exchange pipe. In addition, 18 observation wells were located in and around the well field for long-term observation of ground water conditions.

The individual wells are connected to 20 four inch diameter lateral supply and return pipes. The laterals, in turn, run to a building at the edge of the field where they are combined into 16 inch primary supply and return lines. These lines are connected to the heat pumps which serve Stockton’s buildings. In the heating mode, the loop serves as a heat source and, in the cooling mode, as a heat sink. The heat pumps range in size from 10 to 35 tons. All are equipped for with air economizers. The equipment is controlled by a building management system using 3,500 data points. This allows the College to take advantage of energy saving options such as duty cycling, night setback and time of day scheduling. The building management system also identifies maintenance needs in the system. . . . . .

The system immediately demonstrated that it could carry the entire planned heating load. In the first few years of operation, the average temperature of the well field has drifted upward by several degrees. This occurred because the buildings use more air conditioning than heating. . . . . .

Because of the constant changes to the system, and other energy conservation steps, it was difficult to verify energy savings exactly. Based on extensive monitoring, the predictions turned out to be quite accurate.

Figure 3. The polyethylene tubing and the metal end fixtures for insertion into the MS&T boreholes. (MST)

With this encouragement there was an initial discussion of the system in Mid-September 2010, the scheme was approved by the Board of Curators in November 2010, and 2011 was spent in bidding and awarding the contracts and pre-ordering materials. The first day of drilling was on June 4, 2012, just after the Spring Semester. In order to complete the parking lots – to the degree possible – several drill rigs were used at once:

Figure 4. The use of multiple rigs to speed operations (how many?) (MST)

Once a well had been drilled, and the pipes installed, the holes were backfilled with a grout that included significant quantities of sand, to improve the heat transfer. And the two pipes were all that were left protruding.

Figure 5. After pipe installation (MST)

Trenches were then cut across the lot to allow the distribution and collection network of pipes to be installed. Once the field connections were fused together, the lines were connected to larger transport pipes at the end of the field, and set into a deeper trench.

Figure 6. The connections between the wells and the distribution network. (MST)

The larger pipes were used to carry the water from each field to the heat exchanger/chiller plant, with three plants being located around the campus. All that then remained was to backfill the trenches, tarmac the lots again, and the campus began to return to normal. The last well did not get drilled until half-way through this semester, but the lots are now coming back into use.

Figure 7. Overall layout of the three circuits being used on campus (MST)

With most of the work done on the fields, the remaining work involves the integration of the system into the existing infrastructure, and the necessary changes to the hardware in the various buildings to handle the different ways in which energy is used within them. Much of this change is required since the heating has been, in the past, using steam lines, and these have now to be replaced with the hot water circuit.

OGPSS - The quiet steps of a Geothermal movement

The election is now less than a week away, with two entirely different paths possible for our future as we move past the election into next year. The two approaches to energy are particularly different, but it is pointless to do any further comparison, since the airwaves have (on the rare occasion that these differences are explored) discussed these from all points on the spectrum. But nevertheless it gives an occasion to step aside from Iran, for a week, and to draw your attention to something you may have missed in all this debate, and yet is starting to happen on University campuses that are scrambling to meet that ever rising fuel bill.

In the current debate both sides seem to anticipate that the energy future is rosy. As an illustration, I was struck by a comment just this last week:

"Peak oilers have become almost extinct, destroyed by the arrival of new technologies with the U.S. leading the oil supply change," said David Hufton of oil brokerage PVM.

And yet, in the same week I received another newsletter from Go Haynesville Shale predicting (from Seeking Alpha) that 2013 will see the decline in Hanesville production.

Figure 1. Production from the Haynesville Shale in Louisiana (Go Haynesville Shale )

Now there are a variety of reasons for the decline, a significant one being that the number of wells being drilled has fallen dramatically, as the article recognizes. But that is itself, in part, a recognition of the current economics of the business. I had a discussion, just this past week, with the daughter of an investor who had “lost his shirt” over a natural gas well investment. The difference between the hype and the reality is disturbing, and does not bode well for a stable future. Which poses the question as to what the reality of that future might be?

I live in Missouri, and a number of years ago colleagues of mine evaluated the potential benefits of renewable energy and were left severely unimpressed with the potential for wind and solar in this state. At the time I was not sure what the answer for our state was.

The campus where I worked until I retired, (Missouri University of Science and Technology – the new UMR) had been quite revolutionary some decades ago in starting to burn wood with coal, both as a way of controlling emissions and costs. Now those benefits were disappearing and the campus faced the prospect of finding about $25 million for a new boiler, at a time when state funds are not likely to be available, and which philanthropist wants to fund a boiler? So the campus had to be creative. And it was!

Figure 2. Old Campus Power Plant - the question of what to do with the stacks is unresolved.

Starting in the summer of 2010 the campus proposed the use of a ground-source heat pump system as a method of using the Geothermal potential under the campus to lower the overall operating costs of generating power, while at the same time addressing issues regarding the generation of carbon dioxide, and the use of large volumes of water that are one of the costs of conventional coal-fired boiler use.

The initial proposal was approved in remarkable time and over the past summer drilling crews moved in for the initial drilling of the wells. Unfortunately (but realistically) the greatest amount of open space around campus that can be used are the parking lots. And so s number of drilling rigs appeared as the students left for the summer, and proceeded to drill a series of roughly 600 wells, each around 400 ft deep. The last was completed last month, and the wells were then lined with piping and are currently being connected into a triad of networks.

Figure 3. Simplified illustration of the geothermal circuit.

Basically the system works on the idea that the ground, in depth, is at a relatively constant temperature. (For those of us who have mined in depth the old rule of thumb in the Northern UK was 60 deg at 60 ft and 1 degree rise per 60 ft thereafter – but the geothermal gradient varies around the world). Given this relatively consistent temperature, in winter the cool water (the blue line) can be pumped underground, heated and returned through the red line, from which it passes through a heat exchanger system that provides heat to the campus, while then being returned via the blue line to repeat the process.

In the summer the flow is reversed. The hot water from the heat exchanger/chiller is returned to the wells through the red lines, releasing the heat into the ground and cooling before it returns back to the surface through the blue line, and into the chiller/heat exchanger to provide a cooling source for the campus.

Current estimates are that the initial costs (paid for with a bond issue) will be no more than the cost of that boiler (which wasn’t going to be funded, yet was needed), but that the campus will save, in the beginning, some $1 million in energy costs (the remaining energy will be supplied with natural gas and the boilers will be retired in 2014) and this will service the bond. The funds only allow some 60% of the campus to be initially served, through three separate plants that are set around the campus. In time, as savings mount, it is likely that other buildings will be brought into the loop (though some have sufficiently antiquated heating and cooling systems that the entire building will need renovation first.

Over the lifetime of the system (and there is not a lot of fragile equipment in the loop, so this may be more than 50-years) energy savings are likely to rise to more than $3 million a year, as the energy crisis that we are currently pretending isn’t coming finally comes to pass.

Given the benefits that the system will develop it is not surprising that MS&T are not alone in this approach. In fact they learned of the concept at the time that Ball State was beginning their project. That project has just been dedicated and anticipates, being larger than ours, that it will save that campus around $2 million a year. It also includes some 3,600 wells by the time that the second phase of the program is completed.

The idea is beginning to catch on, and there are a small but growing number of campuses now that are in the throes of the same type of effort, though in each case tailored to the individual needs of the different campuses. Hampton University in Virginia is heating their Multi-Purpose Building, Indiana Tech has restored and powered a Civil War era building, Montana Tech will use the heat from mine waters underneath the campus. In Boise, ID the ground water temperature is a little higher (around 170 degrees) and the city has used geothermal energy since 1983, and now Boise State is joining in with its own plant. As with the Montana project, so the program at New Mexico Tech has also been funded as part of the Recovery Act. Some of the potential benefits of that program have been described by the Department of Energy. However that presentation also illustrates the transience of the funding opportunity.

Figure 4. The budget for the Geothermal Technologies Program (DOE)

Given that drop in funding, it is yet still possible, given the savings projected not only here but elsewhere, that this technology may still catch on and become more widely adopted. I’ll keep you posted (among other things with more technical details).

Another quake at Katla, and some thoughts on Geothermal in Iceland

There are times when I think that the volcanic activity under Myrdalsjokull is coming to an end, then activity flares again, and a threat again becomes apparent. In the last few hours there has been another 3.2 quake in the region of the Katla caldera.

Recent activity in the region of the Katla volcano. (Icelandic Met Office)

A couple of years ago there was a paper suggesting that many of the small quakes are more likely to be due to ice movement, rather than volcanic activity and magma movement. While that may be true of many of the small events that have occurred recently (and bearing in mind that it is the end of the summer, over which temperatures are warmer) the lineation of some of the quakes seem, to me, to be more evidence of more significant activity.

One can look, for example, at the aligned quakes that occurred around Sept 8th, Sept 20th and Sept 21st.


Earthquake activity for Sept 8th, 20th and 21st (Icelandic Met Office).

The question of how seriously to take all this activity is made more difficult to answer by similar levels of earthquake activity that is occurring further west around Hellisheiðarvirkjun. This is the more westerly of the two starred earthquakes on the map below. (The star indicates that the levels are at a magnitude 3 and above).

Location of recent earthquakes in Iceland (Icelandic Met Office)

However the activity at Hellisheiðarvirkjun is not totally natural since there is a nearby geothermal plant at Hengill which is in the process of being expanded from 213 MW to 300 MW of electrical power and 400 MW of thermal energy. Although there bave recently been a considerable number of small earthquakes (as today’s map would indicate) in the region, and the larger one today, the history of the region shows that it has been 2,000 years since the last major eruption there. The plant is about a 20-minute drive from Reykjavík.

I wrote about some of the problems of water injection into the stressed rock of a geothermal site, and the earthquakes that can be induced, some time ago. Jón Frímann has noted that water injection is currently taking place at Hengill, and thus that many of the quakes are man made. In the earlier piece that I wrote I noted that earthquakes up to 4.6 in size had been induced around the Geysers in California, but with the high incidence of quakes that they see, this has not been considered a problem. I have quoted Ernie Meyer on the work at the Geysers in California where he has said that the largest quake they have seen there was a 4.6, and that "there has never been a damaging geothermal earthquake anywhere in the world."

Iceland is a little different, given the more active ground movement, and that the water may induce larger scale ground movement if it lubricates too many of the potential failure surfaces. The plant apparently intends to continue injecting the process water after the heat has been removed, so that it can recycle and regain heat before again reaching the wells for extraction. Earthquakes up to a level 3 are expected, and are not considered of concern. Though as Denise-Marie noted there have now been a couple of quakes that are a little more than that.

Hengill drilled wells down to 250 m from 50 to 70 years ago, but then with more advanced technology drilled down into the higher temperature zone that can be found down to 2,500 m.

Difference between Low Temperature and High Temperature geothermal deposits in Iceland (Sverrir Thorhallsson )

The wells at Hellisheiði are High Temperature, and it has been calculated that the average well flows at 35.5 liters/sec with a power production of 8.7 MW.

Apparently even geothermal wells can blow out, and blow-out preventers can fail to work. One of the wells at the Krafla geothermal plant in northern Iceland blew-out, although the environmental consequences are much less, since the escaping fluid is largely steam and water.

Geothermal Blowout at Well KR-4 (GeoThermHydro )

Time to wait and see again, how things progress.

Will Renewable Energy Rescue Us All - BP and the IPCC reviews

The people of the world are going to continue to use energy. The fundamental question that this future reality poses relates to the sources from which the energy will be produced. The vast majority of the current energy supply comes from fossil fuels, but, whether it is because of the belief that fossil fuels are going to be the cause of calamitous climate change, or because of the belief that viable production of fossil fuels cannot be sustained at increasing rate, there is a recognition that alternate and sustainable forms of energy are going to have to play an increasing role in the energy mix in that future. However the rate at which those energy supplies are brought into the mix, and the levels that they can achieve are subject to considerable discussion.

The 2011 BP Statistical Review of World Energy in recognizing this, added two new sets of information to their 2011 review of fuel use around the world. The first of these documents the amount of commercial electricity that comes from renewable sources, and the second covers the amount of biofuel that is produced each year. Looking at the amount of electricity generated, the greatest renewable source is currently hydro-electricity, for which BP reports:

Rising use of hydro-electricity around the World in million tons of oil equivalent (divide by 50 to get a rough measure of the equivalent in mb/d) (BP Statistical Review)

The report notes that the increase in the last year, at 5.3% this is twice the historical average, has come mainly through growth in the Asia Pacific region. Note also that this is for electricity generation, Biomass contributes more enery, but a lot is burned directly for heat.

NOTE THAT THIS POST HAS BEEN UPDATED

Other forms of electricity generation have also grown:

Growth in the supply of electricity from renewable sources in million tons of oil equivalent (BP Statistical Review)

The greatest growth has been in Europe, and the overall trend would appear encouraging. In terms of the liquid fuels that must be produced to replace petroleum products in transportation BP shows that ethanol is being most actively developed in the Americas, while in Europe the emphasis is on biodiesel. Combined the growth over the last decade is shown as follows:

Biofuel production in millions of tons of oil equivalent (again divide by 50 to turn this into a rough estimate in mbd). (BP Statistical Review)

To put these numbers into context, however, one needs to recognize how small a portion of the global supply that these supplies now meet. With a global demand getting close to 90 mbd, a biofuel supply that is just over 1 mbd is not currently making much impact, although if the growth rate of 13.8% in 2010, were to be sustained, it could start to have an impact in a few years.

If one looks at the global contribution to power, bearing in mind that the category of biomass includes everything from trees, through brush wood to dung requires some degree of husbandry to be sustainable, the distance that these technologies must grow before they are significant contributors can be realized.

Relative contribution of different energy sources to global power in 2008 (IPCC Special Report on Renewable Energy )

The BP review, while providing a widely referenced source of statistics about energy use at present, and in the past, does not cover future use, however. And the quantity of renewable energy that will be available plays a critical part in helping to plan for that future. It is thus of interest to note that the Intergovernmental Panel on Climate Change (IPCC) has just released a report on Renewable Energy. In the summary press release, the report is cited as showing how up to 77% of global energy could be achieved from renewable sources by 2050.

The report has already received some significant criticism but since it is useful to know how one can grow renewable energy to that level, that fast, I did follow up on one of the references. Steve McIntyre notes that it can be traced back initially to Chapter 10 of the report, and from there back to a paper that admits to the 77% only being achievable if nuclear power is shut down, no CCS power plants are built and there are drastic steps forward in the efficient use of energy. Since those are likely unrealistic I’m not going to chase after that. But what I do find interesting is where the IPCC anticipate that the growth will likely come from. And that can be found in this couple of charts, showing the progress to 2030, and then that achieved by 2050.

Anticipated growth in renewable energy sources to supplies in 2030 and 2050 (For comparative purposes the global electricity demand in 2008 is cited as 61 EJ/yrear). (IPCC Special Report on Renewable Energy)

The IPCC report notes that in order for any meaningful progress to be made there must be significant policy changes as well as moves to ensure the adequate levels of innovation will be achieved that are required to make the progress assumed. (Which is in my book assuming that one can legislate technology, which as we have seen with the cellulosic ethanol story is not necessarily so). But one should also be cautious about the speed of politicial change. There is a lesson, for example, that has just emerged from the UK.

Back in 2007 the Department of Energy and Climate Change (DECC) in the UK commissioned a study on the coming of peak oil that has just been released, and which may explain the complacency of the UK Government. That report noted that while the UK is less dependant on oil to fuel its economy than other OECD nations, the oil that it does use is difficult to replace since it fuels some 70% of national transportation. The report looked at various time frames for peak oil (pre-2010; 2010 to 2015; mid 2020’s; late 2030’s) and concluded that only the first two would pose a problem. By increasing production from the FSU countries and increasing investment in production to meet demand the report justified the medium and long term scenarios. (However at the same time the report saw price remaining around $60/bbl, which is unrealistic already). The conclusions included the following:

•While global reserves are plentiful, it is clear that existing fields are maturing, the rate of investment in new and existing production is being slowed down by bottlenecks, the economic downturn and financial crisis and that alternative technologies to oil will take a long time to develop and deploy at scale;
•The UK economy would be initially relatively robust to higher prices; however, if peak oil happens before 2015 there would be negative economic consequences for some of the main importers of UK goods and services resulting in a negative impact on the UK economy in the longer term. If the peak happens later, it would be possible to mitigate the impact through greater end-use efficiency and the production of sufficient quantities alternative liquid fuels.
•Given the uncertainties around the timing of peak oil and its implications for the UK, there are no obvious additional policies the UK government should pursue to minimise the likelihood of a 'peak oil' scenario and to be prepared to mitigate its impacts in addition to those already in place.

In reviewing changes since the initial report, the summary notes that while not believing in a near term “peak” the authors do not preclude a risk of a supply crunch.

The Guardian article notes that the DECC minister is now starting to have a bit of a re-think. This is driven, apparently, by the rising concerns in industry about the growing signs that all in not as well in petroleum supply as the DECC report would have it. But the speed of bureaucratic change in thought means that it has taken four years to realize that there might be a problem. It doesn’t bode well for the adoption of forward thinking strategies. Unfortunately it doesn’t bode well for assuring that the world has enough energy for its needs either.

UPDATE: Bishop Hill has a post on the relatively incestuous relationship between those authoring the report, the trade associations for renewable energy in Europe and the UE management. Not that I am condoning that it any way, but it does give a measure of what may very well define the outer edges of what, if all buttons were pressed, might be achievable. However even the little that I have read and commented on shows that it is a hopelessly optimistic view of what can be achieved within the time frames assigned, and as a result Government which believes their predictions, and the populations that trust the Governments to take care of them, are going to be significantly dis-served.

Drilling for Geothermal Energy

Just as the thread on my TOD post on Drilling was winding down, horizonstar posted a comment about the tools that Potter Drilling are developing for geothermal drilling, with $4 million worth of help from Google. The comment takes you to a Grist post, from which I am now going to pinch the top illustration.

Hole in granite drilled by Potter Drilling using hydrothermal spallation . Note the fine nature of the pile of material removed)

Now (if you will forgive the vanity) I will add a picture from my doctorate, and an experiment that I carried out in 1967.

Hole drilled through an 8-inch thick granite block using a 9,500 psi water jet. (Figure 7.13 in The Book )

Now if you look at the two holes you might think that the top hole is the better, and more efficiently drilled. This post is going to try and explain why in fact it is the bottom hole that is better and will become one of two posts that I plan on writing on the relative performance of different tools in drilling, including ideas such as lasers, electron beams and the infamous REAM. There is a video of the two stages of the development of the Potter drill in an article in Popular Science from a couple of months back that is worth watching, since it explains their idea.


So why isn’t their approach a good one – well there are a couple of reasons, let’s start with the basic idea of breaking rock. Way back when the world used a lot of coal men still mined it using a pick and a shovel. In using the pick the miner would attack cracks in the surface of the coal and grow the crack so that he could wedge out larger lumps of coal, rather than picking out the coal in small pieces. If he did it effectively he would use something on the order of 4 joules of energy to mine each cubic cm of coal he mined (4 j/cc).

If you are breaking out rock from the solid the amount of energy you need depends on the surface area of the rock that you have to form to break the rock out. Assume that it takes 1 unit of energy to hold the molecules across a sq. cm of rock together. If I want to split the rock through that cm of contact I am going to have to break all those connections and (if the process is 100% efficient) this will take just slightly more than that unit of energy to make the break. Now here is the important bit:
Granite split into two 50-cm x 1 m x 1 m pieces

If I take a cubic block of rock that is say 1 meter in size, and split it down the middle I will cut through 1 sq m of rock over the fracture that I create. So with that same amount of energy holding the rock together(which we call surface energy) it will take 100 x 100 = 10,000 units of energy to make that one crack.

Now if, instead of breaking that rock into just two bits I broke it into a sixty-four, by making three cuts vertically parallel to the front, three cuts vertically perpendicular to the front and three cuts horizontally , then I would have split the rock into 64 pieces each 25 cm on a side, but it would have taken 9 cuts of a sq m each, and required an input of 90,000 units of energy to break the rock into the smaller sizes.

Block broken into sixty-four pieces with nine meter-square cuts.

Thus the smaller the size the pieces are broken into then the more energy that you have to put into breaking the rock to make those smaller pieces. Consider that if you are breaking the rock into a fine powder (as the pieces are with the hole drilled at the top) then if those particles are 0.25 mm on a side then the energy input becomes that much greater (4,000 cuts along each direction – 12,000 cuts total at a total of 12,000 times the energy needed if we just broke the rock out in two big bits).

So breaking the rock out in bigger bits is better – but how can we do this with fluids. Well this is the difference between the thermal process and a water-jet based process. With the thermal process what you generally rely on for the fracture in granite is a phase change in the quartz element of the rock that occurs at about 1300 deg C. This causes the rock to spall and has been used in the granite industry for initial channeling around the blocks to be quarried. (It is very noisy and fairly slow – around 14 sq ft/hour of production). The particles produced are very fine, and the energy required is around 12,000 joules/cc.

Water cuts into the granite in a different way, first penetrating into the cracks between the different grains of the rock , and then as that water wedge is pressurized by the following jet, forced deeper into the crack, growing it and breaking the individual rock grains away from the surface. These grains are much bigger (so the hole wall that you can see in the second picture is rougher), so the energy required to drill can be down in the hundreds of joules/cc instead of thousands.

The other advantage that waterjets have (if configured with sand in the water) is that they can drill through any rock the drill comes up against. That is not the case with the thermal lance, since some rocks just melt into globby messes when heated, and that has to be pushed away (ask the folks at Los Alamos about the nuclear powered thermal drill that they invented one time – they showed how to do that). And the question is pushed to where when you are drilling holes thousands of meters deep.

And just to respond to the point about pipe-dreams that was mentioned about these ideas being impractical – Gulf actually drilled to about 5,000 m deep with an abrasive waterjet drill about 1970. So these ideas do have some practicality. But I’ll return to that aspect in my next post.

Oh, and just to show that you can break out meter sized blocks - this was from when we were excavating the rock under the Arch in St Louis to put in the OmniMax Theater.

Breaking out thousand-pound blocks of rock while excavating the Omnimax Theater under the Arch in St. Louis

Geothermal Energy and Earthquakes

Geothermal Energy is one of those sources that is, within normal scales, sustainable, and it is currently being drawn upon, so that relative costs and techniques don’t have to be invented for it to become a viable program. It can, however, be considered to be useful at two different levels, there is the small-scale facility, often referred to as ground source heat pumps and then there are the full-scale power plant types of operation.

We had considered putting a ground-source system into our own home, and I wrote about that, and other family reviews of the technology back in my Oil Drum days. Arising out of that discussion, and comments, it appears that the current cost of systems remain up around the $20,000 to $30,000 dollar mark, which is considerably too expensive for folks such as myself, relative to the energy and cost return that we would achieve from such an investment. However the comments on that article are informative and well worth a visit.
Ground source heat systems (Source)

It is the larger scale operations that I want to write about today. It is a system that is growing, but in the process is stirring more public controversy. Here much larger and longer pipes are drilled down into rock that is much hotter than normal, and the resulting steam/hot water is extracted back out of the ground and used both to generate electricity and for district heating. These are the systems, such as can be found at The Geysers in California, where Calpine runs 15 power plants that generate some 725 megawatts of electricity.

The Geysers meets the typical power needs of Sonoma, Lake, and Mendocino counties, as well a portion of the power needs of Marin and Napa counties. In fact, The Geysers satisfies nearly 60 percent of the average electricity demand in the North Coast region from the Golden Gate Bridge to the Oregon border. The Geysers is one of the most reliable energy sources in California delivering extremely high availability and on-line performance and accounts for one-fourth of the green power produced in California.

There are, however, different ways in which the heat can be extracted from the ground, depending on the nature of the rock which is being used as a reservoir. In the first, and simplest case the rock is already fractured and contains water, under pressure, that can be tapped by the wells that reach down into the rock. The water is refreshed, either from the surrounding volumes, or by reinjection of the spent fluids from the power plant, after the heat energy has been extracted.

How the Geysers get power

Such a system is, for example, being developed in Switzerland. But whenever fluids move and are injected, or removed from highly-pressurized systems then problems, such as earthquakes can result, and this is what generates the considerable public concern particularly when such earthquakes happen in areas that are already prone to earthquakes.

But this is part of the problem, in that the places where the hot rock comes closest to the surface lie along the boundaries of the plates that comprise the shell of the Earth. And these places already see earthquakes – whether in Japan, Iceland or Switzerland. So if one is going to drill into this rock, and then crack the rock between two wells, to provide a path for fluid to flow and gain heat, then you will affect the rock structure to the point that the change in stresses around the operation can trigger small earthquakes.
LASL plans for fracturing between wells to extract heat from geothermal wells

As the fractures grow to generate networks this weakens the rock, and the fluid lubricates the planes along which the rock can slip, so that rock which was already approaching the stress levels at which the rock would move and generate an earthquake now can, and so it does.
Concept for geothermal heating in Switzerland where they plan on using natural rock fractures

Now in almost all cases the stresses would have continued to build until an earthquake finally occurred. And at that point the energy released by the quake would be greater than that released by the geothermal operation (since the stress levels would be higher at that time, and the failure would be more violent). But it is hard to get that concept over to the public.

Basically they see that the geothermal well was drilled, and an earthquake resulted. That it ameliorated a worsening potential earthquake is something that is not easily recognized, especially since the smaller quake can still cause damage (as it has done).

The problem, and the public relations aspect is a significant part of this, is something that needs to be addressed forthwith, since at the moment the Department of Energy is gearing up for a significant investment in geothermal power including new Enhanced Geothermal Systems (EGS).

Before EGS could be implemented, scientists would need to calm concerns about insufficient technology and the possibility of earthquakes at EGS sites. The allotted $30 million would also have to increase in later years to reach the $1 billion the panel report calls for overall. Still, many scientists view the project as our best baseline energy option.

“We’re no longer limited by just discovering the Icelands of the world,” says Jefferson Tester, a professor of chemical engineering at MIT who chaired the EGS panel. The report estimates that by 2050, EGS could be implemented to a capacity of 100,000 new megawatts of power – more electricity capacity than all of the nuclear power plants in the United States combined.

At present the problem that relates earthquakes and geothermal energy extraction is known, and recognized

a major quake requires a several-kilometer-long fault, argues Ernest Majer, a seismologist at the Lawrence Berkeley National Laboratory. Engineers know not to put EGS sites near large or dangerous faults, and the small cracks created by the system itself are not dangerous. “We can’t make faults as big as Mother Nature does … and there has never been a damaging geothermal earthquake anywhere in the world,” he adds.

At Geysers in California, there are about 3,000 earthquakes per month, according to Majer. The largest, however, reached only 4.6 magnitude – big enough to be noticeable, but not dangerous.

Majer is enthusiastic about how education and community involvement can help to allay earthquake fears. The quakes at EGS plants can be controlled and monitored for safety, and better research will help scientists and engineers understand how to make EGS plants even safer, he says.

Explaining the issues to the public may, however, be another story.
(For the record I am working with Dr Majer on a program that could be funded under the EGS program).

P48. Pick Points

Half-a-dozen or so stories of interest:

There has been considerable debate about fossil fuel producers being given tax breaks to encourage production. Treasury Secretary Geithner has suggested that those days should be over, since the companies contribute to global warming. It is perhaps an indication of things to come.

"We don't believe it makes sense to significantly subsidize the production and use of sources of energy (like oil and gas) that are dramatically going to add to our climate change (problem). We don't think that's good economic policy and we think changing those incentives is good for the country," Geithner told the Senate Finance Committee at a hearing on the White House's proposed budget for the 2010 spending year.

I suspect the days of being able to separate the debates on peak oil and climate change may be coming to an end. And yet, at the same time he spoke of the need to reduce the national dependence on foreign oil. The proposed budget would also charge $4 per acre for leases in the Gulf that are nonproducing. But the core proposal is to raise money from the cap-and-trade system that could be used to help pay for the middle class tax cut. The apparent rate for carbon dioxide production that is being bruited about is $20 a ton.

German Chancellor Merkel has said that the Nabucco gas pipeline should not be subsidized by public money. She sees the problem as being one of getting enough gas to supply the pipe, rather than raising the cash, since she anticipates enough private investment.. Germany has long been suspicious of the pipeline. Former Chancellor Schroeder, who is on the Board of the Nordstream pipeline to bring Russian gas to Germany, (as well as the TNK-BP Board) was today in Yugra, visiting the Kamennoe field, where TNK-BP get 70% of their production (40 million tons in 2008 or roughly 800,000 bd). The ex-Chancellor noted that it was one of the most modern fields he had seen, despite the economic conditions they hope to hold production at current levels this year. Italy meanwhile is calling for a high-level meeting with Turkey and Azerbaijan to discuss getting gas from the Shah Deniz field. This is some of the gas that might end up in the Nabucco pipeline.

On a slightly worrisome note, there was an interview with Kate Watters of Crude Accountability about Turkmenistan’s oil production. Worrisome since it has been through ecological concerns that Eastern European governments have sought control of Western investments. And there are areas where concerns are now being raised

Unfortunately, we have seen serious problems with IFI-financed projects in the Caspian region to date. The Karachaganak Field in Kazakhstan is one example where a recent audit by the IFC's own compliance mechanism found it to be out of compliance with numerous air monitoring requirements. Numerous complaints have been filed against the EBRD and IFC for their investments in the Baku-Tbilisi-Ceyhan pipeline, and we have grave concerns about the environmental impacts of EBRD financing at the Bautino Port in Aktau, Kazakhstan, which services the Kashagan field. Among other concerns at Kashagan are threats to the habitat of the Caspian seal.

Completion operations are underway on a well to test multiple prospective intervals in theHaynesville shale. The first fracture stimulated a fourteen-foot interval with 78,000 pounds of proppant. This zone is currently testing at approximately 400 thousand cubic feet per day (kcfd). The Company plans to test this first stage for three to four additional weeks before testing additional intervals. (Note these are vertical wells in the Haynesville gas shale).

One of the big targets for the stimulus package is to improve the national electricity grid, and its ability to distribute power. There are some growing concerns that the investment alone might not be enough. One problem is a recent court ruling said that states could over-rule the Federal Energy Regulatory Commission regarding putting these lines in place. Another is that there are not yet enough standards established for the new grid components, although with encouragement these could be developed relatively quickly. Standards are needed, since there are a number of competing products, for example in the smart electricity meters that are used to optimize domestic electricity use, and legislation may end up favoring one over others.

The TVA is spending over $1 million a day in cleaning up the coal ash spill in Tennessee, with the ultimate bill being expected to be in the $500 - $800 million range.

The Department of Energy is already starting to post some of the steps they are taking to spending their portion of the stimulus package. The initial breakdown into ten overarching programs is first defined and then the subdivisions are broken down into the sub-divisions, each with their own web page. These ultimately lead to the Funding Opportunity Announcements, two of which came out today, as an example:

The first FOA offers $35 million for component research, development, and analysis. The funding will support 20 to 30 projects to develop advanced technologies that will address important aspects of creating, managing, and using engineered geothermal reservoirs. The second FOA offers $49 million to support 5-10 domestic EGS demonstration projects. DOE seeks projects in a variety of geologic formations that will quantitatively demonstrate and validate reservoir creation techniques that sustain sufficient fluid flow and heat extraction rates for 5-7 years and produce at least 5 megawatts of electricity.

More stories can be found at The Energy Bulletin and Drumbeat at The Oil Drum.