so hi everybody i hope you are doing great welcome to this fish that is continuing in the summer uh today we are delighted to have joseph moore with us uh joe is currently a research professor at the university of utah he got this phd in geology and geophysics from penn state university in 1975 and his research has focused on the geology and geochemistry of geothermal systems in recent years his attention that's been directed towards the development of egs enhanced geothermal systems and he served as the principal investigator of the rough river idaho gs demonstration project and is currently the pi of the utah forge project which is uh the topic of his talk today so thanks again joe for accepting our invitation and the floor is yours oh thank you thank you so much can you hear me okay yeah all right great great so so good afternoon everyone um as adrian said i am the managing principal investigator of the forge project and this is an international laboratory for those that haven't followed it it's the frontier observatory for research in geothermal energy and this is really an international laboratory for egs development this is a picture of the ford site you can see it's it's unpopulated uh we'll look at other views we're currently drilling a well near here just off to the right and this is the rig we're using uh for scale the rig is about 160 feet off off the ground and um to the top of the mast so it's it's a large oil and gas well what i'm going to do is just provide uh an overview of the of what we're doing i'll start with some some comments about conventional geothermal systems then we'll look at enhanced geothermal systems and and why utah was selected for the forge laboratory um and then what we're doing to build the laboratory and and where we are currently um i'll try to limit my my uh my notes and conversations about 45 minutes so that that we can have some time to talk afterwards this is just uh a shot of google earth shot of of the area again here's the fort site these are the mineral mountains and we'll we'll talk a bit about them you can see some crop circles down here but there's not much going on in this area that's important it's basically uninhabited not much infrastructure in the area okay so you probably all know about geothermal energy and i won't bore you but low emission base low power is what we always talk about for for geothermal energy but but lately we're we're finding that that that's not the best use uh places like california with their renewable energy standards you know have plenty of energy during the day and from from wind and solar the problem is is really at night when these renewables are are not working and so geothermal is actually becoming a peaking energy so turn it off during the day turn it on at night and it does work vast resources we're going to talk about that relatively high cost before established but but once it is established then the costs are really quite low and a very small geographic footprint we see here on the right an electric generation plant space eating these uh i'm i'm not sure i doubt from where you are but but poinsettias and chrysanthemums anywhere in the west come from this uh greenhouse it's 25 acres of greenhouses spa is the most common use of geothermal energy and then heat pumps this is a hotel in in switzerland okay so there's a there's a broad range of temperatures for for geothermal systems as well as as uses overall geothermal systems span span a range of temperatures from about the global gradient of 21 to 25 degrees c per kilometer to the boiling point and and virtually all geothermal systems all conventional systems follow the hydrostatic uh boiling point to depth curve um basically we typically do not drill deeper than about three kilometers or there are a couple of reasons from this one is permeabilities tend to decrease as we get to greater depths and and the other is is that drilling becomes expensive for uh for what we achieve because permeabilities tend to decrease and water has so little value you know 150 at the value of of oil for example on a per barrel basis right and we have to use these large large rigs it becomes very uneconomic to drill much deeper than this three kilometer or ten thousand foot depths okay so we have heat pumps at the lowest temperature direct use probably the best use of of of water heat pumps don't don't involve water okay that's just heat from the earth for heating and cooling direct use involves water convention conventional systems convective systems and basically up to about temperatures i'd say 150 maybe 200 typically though somewhere around 150 a binary plant that's an organic rankincycle plant we can need to generate electricity and they'll go up maybe 200 to 225. the most most geothermal resources fit into the binary binary field here in order to get the quantities of water we need say greater than 40 liters per second up to 100 we have to pump the the wells above 200 degrees the pumps don't work so that's that's really the practical limit on binary plants uh flash plants um these are steam turbines they're higher temperature mostly overseas typically typically in the 250 to 300 degree range okay um and so these are typically so magmatic environments um around volcanoes and and a few in the u.s at the geysers um salton sea and basin and range but what we're mostly interested here is this egs enhanced geothermal systems or engineered geothermal systems i think that the current use is enhanced so deeper than than we would normally drill and over a broader temperature range covering the binary plant and the steam plant okay basins you'll you'll hear about oil and gas co-production this is something that is being discussed there's a lot of interest in it but but has not gained the traction yet that that we need to all right so conventional geothermal systems if we if we just look at them from you know a very simplistic uh view they have large in-situ volumes that's that that's important and heat transfer is convective and we'll talk more about that in just a moment uh relative to fort site um while while we think of these things well most people tend to these things think of these things as reservoirs and i'll show you a picture in just a minute of what the reservoir actually looks like very few geothermal systems have production for more than three four or five fractures okay and we're looking at flow rates of greater than 40. this is only important because i'm going to use this as a metric for a forge site for an egs reservoir 40 is actually on the low side for a conventional system we're probably looking more like um a hundred liters per second okay and then then production is typically commercial 10 megawatts with one megawatt uh serving about a thousand homes 750 to a thousand homes up to about 800 megawatts the geysers the steam field 90 miles north of san francisco lardarello and italy these produce steam not water and then finally microseismicity it's common uh and it typically occurs at low levels naturally it's also related to injection um micro seismicity is important because as the fractures uh as fluid flows through the fractures that there's cooling the boiling occurs and the fractures start to seal so the micro seismicity tends to keep these these fractures open this is a a well south of uh south of the fort site um not far from where mike has been been working this is this is the thermo site um worldwide an average well is six megawatts biggest is 15. these are these are huge huge wells okay and a 200c with a flow rate of 23 liters per second you get about a megawatt that's that's kind of the numbers we're thinking about nothing to remember just just keep it in mind okay so you all know what a geothermal system is you've all seen them conventional geothermal system you know it's basically a convective system uh the water is is cold it's dense right it flows down existing fractures as it flows it heats up becomes more buoyant and comes up along other fractures we tap it and extract extract the energy the slide on the right is the reservoir so when we think of the reservoir it's not a sponge the reservoir probably has what um fractures like this maybe ten percent of a typical geothermal reservoir is fractured okay so think of this as a tombstone um i mean that's it you can see through it okay so just think of it as tombstone with a crack or two in it okay um permeabilities you know maybe 50 to 100 darcies they have pretty good permeabilities when you look at fracture permeabilities uh when we look at forges we're looking at got 30 micro darcies you know there ain't no permeability in in this environment and and that's really important so with this background you know let's ask the question why forge why are we looking at enhanced geothermal systems and um jeff tester and his colleagues at mit in 2006 you know put together a seminal paper on on enhanced geothermal systems jeff had had worked at phantom hill you know the first site that that really got egs going and the to me the major conclusion of this this paper that came out in 2006 was if we look at the the energy attempts at three to ten kilometers then even two percent of this energy would provide more than two thousand times your yearly us needs and and this caught the attention of politicians and especially back east because geothermal really is non-existent back east except except for these heat pumps and then a few years later um about 10 does put out their geovision report which basically was designed to uh provide the background against solar and wind right it was the geothermal vision the program how do you get there and they set a goal of 60 gigawatts 60 000 megawatts that that's uh by 2050. you know that's a lot
of energy okay right now we produce two and a half gigawatts and let's just assume you know that's just the the base plate that on the turbines it's not actually what we produce but you know you know we can count all all of all of the megawatts capable of coming out of these conventional geothermal systems with california nevada and utah being being the top three one one in hawaii some of you may have seen that it got covered by lava it's been dug out and it's working again there's one in idaho that you know there are a few around but not very many um but and if you look at than the natural systems you know and think of these as hot spring systems all pressures are hydrostatic they all they all come to the surface at some place okay and so we can look at hot spring systems there's no way we'll ever ever reach 60 gigawatts it's just an impossibility and and the only way to do this is to build our own reservoirs make reservoirs in hot rock okay and so that was that was jeff's thesis we can do this um so where do we go where do we find hot rock how do we do it that's forage well fortunately we can find hot rock anywhere we want to look and and that's critical this is three and this is six kilometers i picked these because we can drill these depths without much trouble 150 is you know i'd say the lower limit for electric generation and and being colorblind i can actually see this color well on the map so so i chose it and and we can see it three kilometers you know most of the um most of the rocket 150 is at three kilometers found in the western states really that's why we have most of the conventional systems and hot springs there the you know there's extensional environment heat is making to the surface at relatively shallow depths okay not much back east but if we go to six kilometers and now we pretty much open the country to to geothermal development uh still at the west obviously very shallow that's very hot temperatures steam plaid type temperatures but but we can move across the country now and get get to washington dc we can build a system in washington this got the politicians very interested you know from from the eastern coast new york politicians became intrigued with the possibility and and so forth took off um if we just look at the western states usgs resource estimation is you know 518 000 you know well beyond the 60 gigawatts uh being available uh so we think we can we can do it and and that was that was important okay well have we ever tried that's um that's an interesting question yeah since since um the early 70s there have been more than a dozen egs attempts and fenton hill was one of the early ones um there have been attempts in england france all over the results have not been encouraging we do not have a system that that we can say we've done it right we have not been able to make that fracture and environment uh i'm gonna kind of speed up a little bit but cooper basin was an interesting experience you know um this was in central australia it's it's tens of miles hundreds of kilometers away from anything you know big prospect area four wells temperatures 240 c obviously doable on the right what i wanted to point out is this is the fractured zone this is the seismic zone that that was documented during stimulation and yet it was only able to produce one megawatt there was less than probably five percent um uh communication be between the fractures so we have a huge fractured volume with apparently no fluid in that fractured volume that's our challenge how do we make the reservoir we can make fractures or open fractures because they're slip here right maybe they're not open but we can create seismic noise so how do we do that that becomes our problem the current status of egs there are no egs systems greater than a few megawatts i think it sults in france one and a half megawatts you know it's not commercial 10 megawatts is commercial none are producing flow rates that are even remotely economic less than 40 liters a second less than a few percent uh fluid recovery from from these systems the fractures that are in these systems are fractures that existed before any stimulations occur these are all hydraulic stimulations i'm only dealing with hydraulic stimulation it's not acid dissolution of limestone for example okay so the fractures that existed when we drilled the wells are the fractures that control fluid and typically one or two and and these fractures can be opened by hydro shearing and thermal effects and on the upper right you can see hydro shearing effect you can see by shearing the sides of the fracture we can create wormholes for permeability and in the lower slide you see a fracture this is an fmi well it's a televiewer but you can see a fracture as a sine wave and over time this group of fractures has been enhanced through cold water injection as we inject the cold water the rocks contract the fracture grows so here we can see what a fracture looks like this was known when we drilled the well okay the biggest issue beside the biggest challenge or the biggest issue besides beside how do we make this fractured volume that communicates within itself and we can extract water from you know at commercial levels is induced seismicity and several projects have generated seismic events exceeding three you know typically up to about 3.5 but in pohang um that was uh that generated a 5.5 when a natural fault slipped okay massive damage it should not have been drilled there nobody was watching it at the time but it happened and and you know this has caused people to rethink right now in in europe and in germany for example in the ryan groban you can't do hydraulic stimulations okay um and the trees it's sensible it's shaking some windows okay so so that's that's created some issues for us so we've learned some things you don't inject into through going faults and so we've spent a lot of time documenting the geology of the area low pressure hydro shearing of critical stiffs fractures may be important critically stressed fractures those that are ready to fail are are important we've got to know where they are and i'll show you why cycling may work uh thermal stimulation may work we we've got to you know this this is critical we've got to be prepared and we have developed a stoplight system so if we have a certain number of seismic events during a certain amount of time we stop and evaluate the two pictures at basel in in switzerland uh in 1356 and and in 2009 the 2009 stimulation stimulated the same fault that wrecked the city you know centuries ago probably shouldn't have been drilled there okay there are three uh really critical areas of research that doe has recognized stimulation and planning basically new well configurations and well designs and i'm going to talk about that we're going to take take learnings from the oil and gas industry for all of these fracture control how do we fracture that reservoir isn't that a simple matter all of the all of the past egs projects have have tried to stimulate large long open hole sections so we drill the well and then the conventional geothermal system the rocks are so so hard um and they don't have problems of collapse and caving uh we typically drill open hole to extract every drop of water coming out of those fractures okay um and so all of those projects i showed you all 12 or 15 of them have taken the same approach drill long long open whole sections right and we're going to use those then we're going to stimulate the open hole sections conceptually it's a great idea practically what happens is the the first fracture that we come to that has any permeability will take the fluid and over time all of the fluid we inject will continue to go into the top fracture the low pressure region and so it's very very difficult to build a reservoir if you can't if you can't create fractures or open fractures below the one that is taking fluid so trying to work in opal holes and plug existing fractures that take fluid and and can produce new ones turns out to be a non-starter so we need new ways of of designing fracture control and fracture isolation and finally we have to predict and monitor changes reservoir management so these are the three areas that we're focusing on okay um doe and swiss are are support providing or are conducting supporting activities but they're looking at mind tunnels the colab project you may want to have somebody talk about it is a project among laboratories and universities in the homestake mine south dakota and there's a similar project in railroad tunnel pedreto in switzerland and and these sites allow models to be tested against fracture and permeability experiments and and this is this is fantastic you know we think this is great um but but we're in these tunnels we're not under pressure confining pressure from all sides and i don't know if the results are scalable these these groups are drilling very very small holes and they're injecting water at the at the rate of i don't know 100 milliliters per minute and at forage we're going to be injecting um 500 gallons per minute and so there's a real question of are these projects truly truly scalable not convinced they are and the well sizes obviously are different okay so let's move to to forge criteria so the doe project initiated in 2014 and the department of energy set up criteria that they thought represented optimal conditions for an egs project um and so temperatures greater than 175 c and less than 225 c at depths greater than one and a half kilometers this temperature range is is basically in the range of the oil and gas tools right the oil and gas is working in this in this range sometimes up in the 200-ish range so so the thought was we could take oil and gas tools and modify them you know to work in forage um we have to have low permeability i mentioned you know 30 micro darcies is pretty low right no so no no fractures that take water um low risk of seismic hazard i'll show you that right for induced seismicity no environmental risks you know to ground water uh to sage grouse is a major problem prairie dogs these problems out west you don't have them and then no connection to a hydrothermal system right we we can't be connected to a convective regime we have to be isolated from that and there were five sites that originally looked at but but fortunately forge was selected at utah and and and one other point here was that it's representative it's got a granite basement and it's got alluvium over it um so we can go to indiana we can go out back east we can go massachusetts we can find granite right so so this is this is really kind of representative of of the conditions that we might find across the country compared for example to newberry volcano right which was one of the sites that was originally considered okay um ford site is located oh it's about 320 kilometers south of salt lake city it's at the margin between the basin and range and the colorado plateau colorado plateau is a stable environment the basin and range is spreading and so it's an extensional environment uh faults tend to be nearly vertical right and and and normal in nature okay you see some of the groups working with us these are private groups and public groups a lot of federally funded groups national labs universities okay um so here here's a location one of the interesting uh one of the interesting things about the laboratories it's nestled between a solar field the wind farm and a producing geothermal plant and we can see it here here's the blundell plant produces 36 megawatts so 36 000 homes since 1984 it's separated from the forge site you can see some of the wells here by the opal mound fall talk about that in just a minute and then you can see the windmills here and the solar field there's also a gas pipeline you'll see some from pig farms here it's dirty gas it goes to a pipeline located approximately here and that'll be used for for fuel for gas fire plants okay um the the field that uh mike has been working on mike feller uh co-four is just located outside the picture um in fact it's it's right here co fort there's another field here milford is the nearest community seventeen hundred people rather small very very positive about geothermal and um and its application and of course with a small town like this they're reaping benefits from from the work they receive okay uh the geology of the area is is dominated by a tertiary granite you can see that in green um there are more than a hundred wells some deep and some shallow but there are the black dots okay and we have a tremendous amount of gravity empty thermal you name it it's been done a lot of this was done in support of the geothermal plant in the late 70s and this came online in 84. uh whales at um the blundell plant or roosevelt hot springs pre you know produce about 250 sea water the rhyolites and purples and pink pinkish reds are domes that are less than a million years old it tells us there's a heat source still cooling somewhere here um i'm not going to dwell on this it's it's a little bit in the weeds but just a picture of typical granite and typical metamorphic rock which occurs on the the western edge of the mineral range if we look at at the composition they're all basically composed of quartz uh plagioclase and and potassium feldspar in green it's not important that the rocks vary what is important is that the compositions are very similar and the mechanical properties of these rocks are are very similar and that's that's the only takeaway of that okay um so the the contact between the underlying granite which is tertiary and age and the younger younger sediments uh dips about 20 25 degrees to the west and you can see seismic reflection here and you can see it here as well and and this is important mainly be because um basin and range structures in west tend to tend to be vertical and and at forge this this fault has been rotated down to the east okay that's important and and since it's been rotated the the geomechanical studies and and our seismic data uh suggest that this rotation has caused this portion of the fault to become locked it doesn't have a tendency to slip anymore and that's what we want why right we don't want to trigger faults that could slip the active portion of this fault is out in the middle of the basin somewhere so this this is good this is this is what we're looking for here okay these are the measure temperatures here a couple of wells uh the fault was exhumed brought to the surface eroded and then sediments were deposited on top of it the deeper structure is interesting this is a mt magnetotolurics not going to dwell in this is that by a phil wanna maker what is interesting there seems to be a deep pipe-like feature just to the east here uh in the in the just just for information we actually can't see a pointer if you if you show something i i think it's okay if you just describe it but we can't see the pointer you see uh a yellow green um uh thank you a yellow green zone a pipe like feature that extends you know 20 30 kilometers depth um that that is underlying the roosevelt hot spring system which we would suggest is providing fluids and gases and then to the west of that we see uh under the forge footprint most of that is is high resistivities 375 plus three with a little bit of basin fill above it and and this basically says this is a low permeability water poor environment for kilometers below us you know the oe wanted low permeability here it is okay um the the opal mound fault is an important fault um we can see here the blundell power plant and the whales and then to the west we see the forge site um if we look at um pressures we see that the pressures um in in red on the upper right are higher than on the western side of the upper mound so the opal mound appears to be a hydrologic barrier pressure barrier and then if we look at temperatures we can see that east of the opal mound the temperatures tend to be nearly vertical with depth whereas to the west 58 32 is a good example the temperatures increase uh with temperature so we have a convective gradient versus a conductive gradient and we see that the two are different seismically we have been recording since 1981 here university has done this and you can see the seismic events uh up to nine 2016 they're in gray and more recent events in red there are no seismic events uh below the forged footprint okay this is what we see today we you can see our drill rig we're drilling this deep well um i'm going to put it in feet we'll drill to 9 500 feet we have five other wells 78 it's 3 200 feet 68 a thousand 58 7 500 and then a 9 000 foot well 56 and so these vertical wells will be used for seismic monitoring the um the the central piece centerpiece of the the resource will the reservoir will be two wells labeled 16a and 16b 16a has been drilled it's shown in in white it was drilled vertically to about 6 000 feet and then horizontally along this dash trajectory right 16b will be drilled on top of it these are the wells that will be stimulated and we will be monitoring at reservoir depths for seismicity okay you can see a little blip here near the top of the temperatures gradient and that's due to ground water at shallow depths um i won't i won't go into this but but the red or pink outline shows us that the the water this groundwater is actually um subsurface aquifer flowing along permeable horizon from roosevelt hot spring so it's subsurface discharge uh of the resource water and here's a composition it's basically a low uh a low ph low low salinity water it will be used for circulation testing later um we we log extensively all of the all of the wells and probably one of the most important logs is the fmi log formation micro scan scanner log it's a resistivity log and a little bit of mud gets into fractures and those fractures are then recorded based on their electrical conductivity okay resistivity and so the fractures are seen as a sinusoidal wave okay imagine that we've gone down a tube and we have pads and we're we're monitoring resistivity or conductivity along the pads and then we just open up the tube and that's what you see here on the right we've opened up the tube and you can see the pattern there are 2000 fractures that we've seen naturally in the granite most of them dip about 60 degrees or so you can see the most of them are in the center of the graph ranges from 0 to 90 most of them strike about north-south more important though is where are the stress directions and here you can see an induced fracture an induced fracture is caused just by cooling produced as we put cool water into into the well to drill okay and that's an induced fracture you can see a natural fracture turns out these induced fractures are typically north 25 east and they're vertical and and you can see here pre-injection before we inject it you can see a trace of what looks like an induced fracture on the left on that fmi log and you can see that after we stimulate it opened up why is this important this is important because these fractures define the stress orientation for us and so the maximum horizontal stress in this case northeast southwest the minimum horizontal stress is approximately northwest southeast if we're going to open fractures and and we want to drill into those openings we want to drill perpendicular to the maximum horizontal stress so in this case we want our wells to be drilled from the northwest to the southeast perpendicular to the maximum horizontal stress okay and those fractures then that are nearly perpendicular to the maximum horizontal stress are going to be the easiest to open in the stress field okay we've done stimulations we've done them in this first well and we've done them in later wells this just shows a typical breakdown curve on top you see pressures increases fracture curve rock failed and and the curve just decreased um and you can see the earthquakes and the lower one the only thing i want to point out here is these are very low pressures these are surface pressures very low pressures to cause these these openings which tells us you know we we should be able to stimulate large numbers of fractures now come some of the the more difficult problems we use the the fractured data to to generate um what are known as discrete fracture networks um so these are dfns they're they're sort of hypothetical you know they're stochastic models you guys get that and and these are just four models right single fracture two fractures more fractures and the model that that we're currently dealing with has about 2500 fractures so it's a complex model and it's based on the locations of fractures in in the well that we measure and fractures we see on the surface obviously a vertical well is not going to see many vertical fractures so we have to use other data as well and then we try to get a sense of how good is our dfn by doing a history match of the injection data and you can see on the right this is that that plot i showed you where the fracture opened and you can see we get quite a good match does it tell us these are really the fractures that are there or opened no but we got a good match you know at least it's consistent it's it's a good step um here's here's uh two models using the full dfn network and and one of the really critical questions is what is going to be the height and width of the fractures that that are stimulated that's that's really important right we need to know how far apart are we going to stimulate and and both of these have the same total volume but you could see at 20 perils per minute 1800 seconds 30 minutes or so you can see that the hydraulic fracture is shown in red got it's only like 30 30 meters high but the dfn model suggests that fractures with apertures greater than 0.2 can extend maybe 200 meters up whereas at 40 barrels and uh per minute but but at half the rate you can see there's downward growth of the fractures and that that's critical to understand and we need to figure this out okay so that's the kind of modeling we're doing um in in the fall and hopefully in a few months we're going to stimulate three zones at the toe of the deviated well 16a you can see on the left a picture of the well with the casing program in it and the 65 deviation first time such a highly deviated large diameter well has ever been drilled for geothermal purposes okay and then on the right you can see three fractures there'll be three three stimulation zones there'll be two encasing one an open hole which is about 75 meters long 200 feet long and and so the question is how far do we space those stimulations so so the general approach is pretty simple we drill the first well we've done it that's the injection well we will then stimulate some zones in that well and we will monitor the zones using using our deep seismic well so we'll be at this this level this depth monitoring using strings of geophones and nodal arrays okay and and we will find out what that seismic cloud is now because the rocks have no permeability it's pretty obvious that if we generate any permeability it's got to be in that seismic cloud right so the next well will be drilled into the seismic cloud we'll then have two wells we will stimulate up and down pump cold water from the ground water into the injection well pump it out of the production well we'll cool it but we could run it through a turbine generator and generate electricity for ourselves we can't go into the power lines and then we'll pump it back in so this is this is cyclic unlike the the oil and gas fracking environment where you inject water into already saturated rock so we're just going to be cycling this water around and around if we're right maybe we'll lose 10 percent that we have to make up so that that's the overall goal in 2024 right now the project ends and um we are working with with our congressman and doe to extend the project so that those of you on the call can have some place to do stimulation testing circulation testing seismic monitoring all right so how are we going to do this well one of the things that we've learned from the oil and gas industry is we have to isolate portions of the well and we're going to do this by casing or running running pipe into the whole well from top to bottom so no open hole we're then going to put plugs in the well these are presumably movable plugs and on the left you see a bridge plug a bridge plug is a tube with a hole in it okay and and i'm sorry it's a that is a bridge plug on the lower right you see a packer the packer is a tube with a hole in it okay and the bridge plug is solid think corks so we put the bridge plug at the bottom of the zone we want to stimulate and perforate with charges and we put the packer on top we run a tube through the packer and we pump water into that zone and and by that will allow us to hydraulically stimulate the rock behind the casing okay that's what we've done before while we thought oil and gas tools would work you can just see the differences between a new one and a failed one and i can tell you right now we've had a hundred percent failure on these tools so we're working hard to develop tools based on the oil and gas approach that will work to allow us to stimulate the rocks and build a fracture network um so where are we in terms of current status we we have a platform for optimizing drilling technologies we we drill faster um basically we've been predicting drilling some of these wells in 30 days we're drilling sorry predicting drilling these wells in 60 days we're drilling them in half the time so huge advances in drilling technology using different bits using mechanical specific energy and that's important because even a conventional geothermal system 50 percent of the cost is in drilling and if i can drop the drilling costs by 50 percent this is going to be very important we've got an extensive geoscientific database that you can access we're drilling wells for future r d deployment seismic monitoring obviously we're providing data for stimulation design and r d implementation and obviously there are r d opportunities that forge is providing for technology development currently forge is working on the first solicitation negotiations and there's about 50 million dollars that will be negotiated for 17 r d projects a new solicitation will be coming out in about a year all of this data is available on the geothermal data repository it's an open ei repository you can google it you can go to our website utahforce.com and you can find links to it so everything we have done is public domain and i've abused my time but i thank you for your attention uh thank you very much joe thank you for the great talk for this overview of the first project um so we have yeah we have time for for questions um just feel free to mute yourself and ask your questions anybody who wants to stay on i'm happy to stay thank you really appreciate it can i ask a couple questions this is mike go for it mike hi joe very nice talk it's good to see all this that's going on um i have a few questions what you you talked about minimum maximum horizontal stress you think it's a strike slip stress regime where does the mit where does the vertical stress no no i think it's a vertical i i think the vertical stress and it's uh well i think it is an extensional regime the faults are are a vertical um so what what i didn't discuss much is if we looked at the map to the west the the youngest falls cutting the alluvium tend to be nearly vertical and then sold out so there are less than 15 to 80 000 years old the open mouth fault is vertical there are strike slip structures the negro mag magley fault apologize is is an east-west structure and we're seeing seismic events on it and to the south of milford we're seeing some east-west structures but we think dominantly it is a it is an extensional environment when we uh when we stimulated i guess i can go back uh there we go you know when we stimulated the the cased hole um we specifically picked a zone with with optimally or what we thought were optimally oriented fractures you can see from the seismic events that that we did open them we only had one one geophone so i don't have you know locations we'll have that next but we clearly did open them it clearly met you know our understanding that that these northeast trending fractures are going to be opened so your your plan i just wonder how much effort you're going to be putting into understanding the stress field you know at basil keith evans and others did a lot of work at trying to look at the stress field as a function of depth which aided a lot in the interpretation of the seismicity is there going to be effort put into the understanding that both the stress field and the variation with depth so right now the best we can do uh and that's a great question you know we've been dealing with it um uh pendu and john mcclellan are working hard at that we are logging we're doing ubi and fmi logging to look at orientations induced fractures we have them basically from 3 000 feet down so so we're looking at rotations it probably is a little bit rotated the stress field but we're looking at at the fracture record going going down we're trying to uh we will be doing in in the next deep well uh we hope a series of uh stimulations up the hole to see if they vary uh so far the two holes have given us very very similar uh uh information in terms of closure stresses um yeah we're going to keep looking at it it's it's hard you know it is yeah um we've used televiewer data from roosevelt hot springs and is giving us the same same orientations um i agree we're trying everything we can um where you know we're doing leak off tests where you know we'll do other stimulations the these were very small but um you know they are helping with closure i think at this point what we've learned is we cannot make a reservoir using uh just based on hydraulic fracturing you know we've got to use the the existing fractures the dfm in fact we tried we did three stimulations uh the third stimulation had some poorly oriented fractures and and but very little fractures and we pumped and we pumped and we huffed and we got to 6 000 psi wellhead and the packer failed and we could not stimulate anything in fact because the packer failed we stimulated the lower zones again so so we know that that does happen but we couldn't stimulate anything our plan right now is we we need to isolate sections that that have large numbers of these northeast trending natural fractures and do the best we can to open them so your intention is you mentioned hydro sharing and and i wonder are you going to inject above the minimum compressive stress or are you going to inject at below um that's still a good question you know right now we're looking uh we're looking at probably pumping 25 barrels per minute um we we want to see what happens you know we're open to what those pump rates will be pump times part of its logistical you know what can we get on on site uh to do the stimulation uh we're not going to hit it very hard at this point i see that oh unless you have another question well i i i'm going to defer to other people so why don't you okay we can go back otherwise i see that chad and they may have their hands up maybe we can start his chat hi there yes uh thanks for the presentation it's excellent um i have a number of questions i'll keep it just um really just focusing on drilling um i know the dto uh mentioned earlier in the year that that you all had a great um experience drilling the last hole and beating your schedule um given the the issues that you're you're facing with some of your tools not actually meeting their uh advertised ratings um i'm kind of curious how that happened and and and how are you dealing with these tools are you actually developing ones yourself are you working with like a service company great question so so in fact we just set a new record even though we have two failures um the well we're currently drilling seven uh 78b 32 will be the is the hottest and deepest of the wells we're drilling because it's 9 500 feet uh i'm anticipating close to 250 to 275 c at td so we're working with texas say in mu and and we are using mse you know minimizing mse mechanical specific energy and we are using pdc bits that that have been specifically designed for the granite so the granite doesn't have fractures you know the fractures aren't open and and we just finished the bit run of 2100 feet so we have motor problems mud motor problems we had a rotary steerable system that that failed right now we're using mud motors we're trying to keep high temperature mud motors on site but we're we're drilling a hole right now of ten and three quarter inches so we're drilling a large hole that will accommodate a seven inch casing string but but we have to have this large hole because a fiber optic cable with a strain a dedicated strain cable fiber this is celixa and and high-res high-resolution seismic cable dash cables will be cemented in the annulus of that seven inch casing and then we'll drill then we'll drill just five eight eight five five inch hole you know or close to six inch hole below that okay so these these these packer and the the packer and bridge plug issues are real issues okay question is how do i get around that the drilling issue we managed to get around that because the mud motors you know we're getting long runs out of them before they fail long runs out of the the pdc bits before they fail and so we're making up the time because we're not tripping and the big issue is how much time do you spend coming out of the hole and going back into the hole to change a pit and at at the depth or at about 7 000 feet it should take 10 hours to come out and go in and you know our total cost is like 70 000 a day so if i can cut costs cut bit repairs uh you know just people don't know these these bits i don't know 40 000 every time i i destroy one and we're destroying them you know these mud motors they they have to be rebuilt and and so we have to pay for that it's expensive um you know we have to keep the whole vertical um or as close to vertical this one i think deviated 20 feet 24 feet so far so basically if you're standing on the rig floor it's still just about at the edge of the rig floor uh my my allowable deviation is 250 feet so um that that's the problem to answer your question i think what we're going to end up doing is we're going to probably take a metal bridge plug uh maybe one of the halliburton or baker youth and and we'll probably do the three stimulations well for the open hole stimulation just do open hole we're not gonna run tubing we're not going to run it through tubing we're going to just do an open hole gives us a better handle and frictional losses uh you know longer hole for less frictional losses so we'll do the lower one open hole then we can come up and um put a put a packer sorry bridge plug above that perfe above the open hole at the base of the base of the casing perforate stimulate open hole and then then i have a choice and we have made the decision i can either try to move that packer up and do it again or i can leave the packer there and and set another packer above the last stimulation there's an advantage of that because when we drill the next well the parallel well i can then pump water back into the uppermost perforated zone and see if it comes out know exactly which zone took the water but i'm hoping we we have contracts out for sliding sleeves um and and for um taxis this 65 degree well you know nobody's ever done that geothermal wells are never beyond 30 degrees 30 to 35 degrees deviation the reason is you can always run a wire line under its own weight turns out you can't it's 65 degrees you got to run a taxi or to even log these holes we're running through the bit because the temperatures are so hot you know we can talk about this offline too temperature's so hot we run pipe down the hole we run the tools basically in that pipe with a drill bit at the bottom with a big hole okay we get and so we're pumping water all the time keeping that well cool tools a million bucks a shot i can get insurance for 50 of that i can't afford to lose a tool so we pump the water down they don't and you know they don't last more than 350 f my temperatures are you know twice three times that so we pump water down the hole we extrude or pump out the tools and then we come back up and so that's how we have to log these holes through the bit logging you know and keeping the hole cool and that takes time but we can do it you know we're finding tools that work mud motors just working with you know hot mud motors they go to 350f you know mwd measurement drilling same thing and so you just have to keep the whole cool right now hopefully in a year before we drill the next one we'll have some tools i i think i think we've got to figure out how we're going to stimulate and keep the fluid you know a big big question is we want a a massive sorry you know you want uh you want a reservoir that looks like this right but you run your uh well into that reservoir the fluid is always going out the top zone doesn't matter what you do if you have multiple zones food's going to go out we've done these calculations there are some publications 50 to 70 percent of fluid goes out the top zone the rest are it to lower zones crap that doesn't that doesn't help me i've got to have that fluid circulate through this reservoir extract the heat from it um and basically for a commercial setting i need to do that over a 15-year period without just without removing all of the heat oil and gas for well two years you made your profit you put it in a truck and off it goes right and and so you can afford to do multiple multiple drafts and and horizontal legs at the at the cost of a geothermal well you're looking at penny and a half a kilowatt hour you're probably somewhere around around 15 years for well replacements you know we're looking at that um so so there has to be a network of interconnected fractures in which the fluid movement is slow enough to extract the heat i'll never use up all the heat but you know because mostly he's in rough but i've got to be able to extract the heat at a relatively slow rate pumping out the production well and and build up enough profit over time right to use that well for for a long period of time so those are all commercial issues that that really have to be dealt with yeah drilling drilling sounds like no easy task indeed amy you want to step in yeah this is actually a good slide for my question um in terms of first of all it was a very interesting talk and what i want to ask about is uh numerical simulation or modeling uh you mentioned these discrete fracture networks being a kind of stochastic model and you mentioned a lot of data and so my question is um would it be how useful would it be to have a first principled physics-based model of the reservoir which includes flow and geomechanics and fracturing um informed by the data i assume there's some parameters in your dfn model which are the data but if you had a real high fidelity model would that be useful and if so uh where are you with that or or where why not good question we're using a basically a commercial code called excite and this is an itasca code itasca is a a rock mechanics company and so they do a lot of mine work and and if we want offline i can give you uh or i can send you uh the input variables that we're using here okay um obviously this i think more is needed but this is what we're using at this at this time we're also using um code falcon which is um an idaho national lab code welcome f-a-l-c-o-n and and again input but you know a lot of the inputs are coming out of the air this is you know based on based on experience for you know the fluid characteristics um relatively clean water what what we think is the permeability we look at we look at apertures and earn based on the fmi logs and they're an order of magnitude above this so you know we have to choose what we believe is a a reasonable aperture i but i can send you the data that that we are using i think i think additional modeling and would be useful some of the labs are in fact several national labs we'll be using the data to try to improve the parameters that that we are using hopefully that will be helpful um but i but i point you know i i use this for for actually to to get to you know to address your question in a slightly different way here's the same volume being injected at two different rates with the same parameters under other than the rate right and and you see one going down and one going up i don't understand right so there's some process missing and that's the models don't account for yeah yeah and i don't know whether it's just the fluid property is dense and it's going down we don't know that um pendu i can send you a few uh a few papers there'll be a few papers out at stanford last year and that geothermal rising i think it's called now right and energies so we've got some some information that's coming out uh i think definitely definitely we need better resolution i don't know how how you would use these models to build a stimulation program at this point i mean if you if you had a high fidelity model and you performed stimulation in the field and then tried to reproduce it in the model you'd learn a lot about how bad your model is you would you would so right now the best thing i can do is try to match some of the injection data all right you know we can but it doesn't tell me really how good the bottle is yeah mike had another question yeah if it's okay i wanted to ask about this i was curious about why the 40 barrel per minute stimulation went down do they have any interpretation of that no okay i mean you know what one interpretation i would have is that you know the water is going to heat up as as it's injected and when you inject at a higher rate it's not going to heat up as much and therefore buoyancy could make the fluid want to go down you know when you injected a lower rate buoyancy you know the water may heat up and the buoyancy may make it go up you know there was the the classic experiment at cornwall in the united in the united kingdom well they had downward growth and there's a really nice paper written about that that has to do with the stress gradients but but it it wouldn't vary their model wouldn't vary with with injection rate and that that's why i was curious because we saw this at fenton hill yeah um in one in one region of the fenton hill injection the seismicity grew sort of like your left side and in the other region actually it was just a little deeper it went down dramatically and it didn't go up at all and i have an explanation of that that has to do with thermal gradients which i won't go into but but it was a really curious result and it made us abandon the deep and deeper part of the reservoir um so understanding this better is really important i think well well it is it is and and you're probably correct you know i suspect it is a density issue but you know right right now we i don't feel comfortable about you know choosing choosing a rate uh for this we will get seismic data and i think we're deep enough in in in our geophone strings you know they're good for 200 c but you know i think we'll be deep enough to get a real sense of whether the water is uh you know moving downward fractures are opening downward or upward and and so that's one of the the reasons we do want to run the test but we're also logistically limited that you know what rates can we physically pump on this site and you know what what are the seismic record going to look like how much seismicity are we going to see it's really experimental we've never done more than 15 to barrels per minute so really low rates yeah i mean this is an interesting result and i um have they written anything about this i mean a task is first rate so i i assume they thought about it uh a task is putting together a a paper for um for grc geothermal okay geothermal rising so in october whenever it is yeah and at bronco i don't know if you know bronco i can't i i've heard him give it i've heard him give several talks before yeah he's actually leaving that yeah yeah i i think yeah i think the work is credible um but but we have really have to look look at the input you know the geologic input as well yeah i've never felt comfortable with these discrete fracture network models because you know you're making assumptions about what the what the rocks are but absolutely itasca uses them and they and they i guess they keep using them because they must work in certain clients in certain environments well i don't know that i have anything better so we're making yeah it's about cohesion and you know friction angles and but so these dfns are coming from golder and and so elite defenilla is working on okay she is bringing tom doe you know obviously father of fm you know dfm model is is is working with us to develop them and this is i think 600 from top to bottom meters so give you a sense but if i just look at this it's too wide i'm not going to get very many stages in a well i you know if i if i don't want to overlap significantly can i ask one more question um in your one of your your perspective views of the site you showed seismic wells and it you know made it gave the impression that maybe the seismic network was on one side of the of the um the main wells oh is that so there's nothing going to be on the other side of the of the inject of the um yeah i guess you're going to drill to the south to the to the right is that right to the bottom right we we have drilled along the dotted line that exists ah okay so that's why the seismic network is the way okay i was wondering why there wasn't any seismic network to the upper left of the of the plot but the fact that you're drilling these horizontal or sub-horizontal wells makes it clear but but 56-32 is a seismic monitoring level yeah so we'll run geophone string in it 58 is a seismic monitoring well 68 has a broadband accelerometer in it but it's only a thousand feet and 78 b will be a seismic monitoring well we have we have broadbands generally surrounding this area we will have a nodal network on top of the stimulated zone as well uh once we've um so we're we'll be using avalon geophones probably temperature slumber j will be run we'll actually have two groups slumber j will be running the geophones in two of the wells on their string and um ges geoswiss uh ben dyer you're probably right oh yeah yeah i know ben yeah um geo swiss is providing at no cost to me a third string so we'll have these three strings uh running simultaneously two sets of interpretations overnight uh following following it during during the stimulations so i think we'll have have good real-time information once once we pull those geophone strings and we're probably looking at 12 geophones on each string once we pull them we'll go back in and replace them with just two geophones two avalon geophones on each string and just run it back in the hole and leave them we have 78b has a solixa cable or will to 8500 feet uh 5632 has a cable down to 1200 feet mainly because i broke it um so that that so so where's the solicitor tool going you said 78b yeah so we're drilling we're about 7 six hundred feet now maybe a little deeper so we will case uh seven inch casing at eighty five hundred and that's elixir cable with the stream meter and the you know it has single single-mode multi-mode fibers and their high-resolution constellation cable will go in cemented in the annulus of the um of the 78b production casing would they be doing temperature monitoring on that cable as well yes yeah yeah because that could be kind of cool if they can get a temperature signal now we are working with um two uh of the r d performers we haven't negotiated yet uh but i can tell you that both of the in fact there are three performers two of them have proposed to run uh fiber optic cables in in the 16b well which would be parallel to the 16a and so we're looking at running two different sets of cables is is bjorn paulson running anything in he's got three components uh he's part of one of the one of the projects okay i would think he'd be involved but yeah i can tell you one of the one of the projects is um we're still negotiating but it is a combination of shell and austin texas austin sharma and the other one is rice and i think paulson is on that but uh rice and who's running that one jonathan ajo okay i i don't know yeah so so basically one is proposed to shell pack a flat pack using shell technology the other as used proposed to solixa pack okay and then we're also looking at running a dedicated strain meter in the vertical section of that well fiber fiber optic so i think we're well covered the the seismic work uh chris christine pankau university utah seismic stations who is basically the hazard person in utah is is primarily running the surface and the post hole instruments working with jim rutledge who worked at los alamos for years and um then schlumberger on the downhill stuff we're working with uh peter meyer ges group on the down hall work as well so i think we got to cover ernie major is involved with some of this who else um who else uh julie shimada will be involved with some of this and for long-term monitoring was it esg can i get that right i think it's eg yeah esg canada right yeah yeah yeah engineering science group yeah right we'll be looking at long-term monitoring yeah yeah great discussion great uh is there any uh other questions we've already run way past the hour but uh i'm sorry that no no that's great that's great discussion we're very happy about it okay if anybody wants to send me an email you have it um send me email like i said the data is all public some of it may not be curated yet in the gdr but if you want to know parameters for the models that we've been using in excite um i'm happy to send it to you that's great thanks i'll stop the recording here um i think we can we can thank you again for the for this presentation thank you really appreciate it we really kept
2021-07-26