{"id":24493,"date":"2026-10-31T07:30:00","date_gmt":"2026-10-31T11:30:00","guid":{"rendered":"https:\/\/www.autonocion.com\/us\/?p=24493"},"modified":"2026-10-31T06:07:31","modified_gmt":"2026-10-31T10:07:31","slug":"11200-foot-geothermal-well-utah-11-days-555-degrees-155-hotter-several-gigawatts","status":"publish","type":"post","link":"https:\/\/www.autonocion.com\/us\/11200-foot-geothermal-well-utah-11-days-555-degrees-155-hotter-several-gigawatts\/","title":{"rendered":"An 11,200-foot geothermal well drilled straight down into the Utah desert in under 11 days hit rock above 555 degrees, 155 degrees hotter than the rock feeding its driller’s new power plant one county south, and an outside review put the field at several gigawatts"},"content":{"rendered":"

If you’ve read anything about geothermal power in Utah lately, it was probably about Cape Station. That’s the plant in Beaver County that started selling electricity at the end of September, and we covered it when its first 33-megawatt block hit commercial operation<\/a> a day ahead of its contract.<\/p>\n

But the hottest hole Fervo Energy has ever drilled isn’t at Cape Station. It’s one county north, in Millard County, at a site the company calls Blanford. And the rock down there is a lot hotter than the rock feeding the plant that just switched on.<\/p>\n

The well is called Cottonwood. It went straight down to about 11,200 feet in under 11 days, and temperature logs at the bottom came back above 555 degrees Fahrenheit. The company says that’s the hottest well in its history. It first announced the result at Stanford’s annual geothermal workshop earlier this year, then repeated it in its first quarterly report as a public company<\/a>.<\/p>\n

That’s a company record, by the way. Nobody at the company claims it’s the hottest geothermal well anywhere, and I’m not going to claim it for them.<\/p>\n

So why does 555 degrees matter?<\/h2>\n

A quick refresher if you’re new to this. Fervo’s kind of geothermal doesn’t go hunting for natural pockets of underground hot water the way older plants do. Its crews drill into hot, dry rock, crack it open with the same fracking equipment shale companies use, and pump water through those cracks so it comes back up hot enough to run a turbine.<\/p>\n

Basically, the hotter the rock, the more energy every gallon of water carries back to the surface.<\/p>\n

Fervo’s CEO, Tim Latimer, put a number on that when he talked to analysts on the company’s August 12 earnings call. Moving from 400-degree rock to the 430 degrees that Cape Station’s second phase is designed around should squeeze about 27% more power out of the same well flow and the same steel on the surface, he said. Blanford’s rock sits more than 125 degrees above that 430-degree design point.<\/p>\n

Now, I wouldn’t stretch that 27% in a straight line all the way up to 555 degrees. Nobody has published a power estimate per well for Blanford, and I can’t do that math for them from a press release. Still, it’s pretty safe to say a well in 555-degree rock carries a lot more heat than one in 400-degree rock, and more heat per well is how a geothermal company gets more electricity out of every hole it pays for.<\/p>\n

Here’s how Blanford stacks up against the other rock Fervo has drilled into, using its own figures.<\/p>\n

\n
\n
Project Red, Nevada<\/div>\n
365\u00b0F<\/div>\n
The pilot plant, Fervo’s first enhanced geothermal project.<\/div>\n<\/div>\n
\n
Cape Station Phase I, Utah<\/div>\n
400\u00b0F<\/div>\n
The rock behind the 33-megawatt block selling power since September 30.<\/div>\n<\/div>\n
\n
Cape Station Phase II design<\/div>\n
430\u00b0F<\/div>\n
Average temperature for the 400-megawatt expansion due in 2028.<\/div>\n<\/div>\n
\n
Sawtooth 7, Cape Station<\/div>\n
460\u00b0F<\/div>\n
19,448 feet of measured depth, drilled in 21 days.<\/div>\n<\/div>\n
\n
RECORD<\/div>\n
Cottonwood, Blanford, Utah<\/div>\n
555\u00b0F+<\/div>\n
Straight down to about 11,200 feet in under 11 days.<\/div>\n<\/div>\n<\/div>\n

There’s one more number in there that I think gets overlooked. Blanford’s geothermal gradient ranks above the 95th percentile of deep sites in the western US, according to the company’s temperature logs. Gradient is just how fast the rock heats up as you go down. So the ground there warms with depth faster than at least 95% of comparable spots in the West.<\/p>\n

The rock is easier to drill, too<\/h2>\n

The other surprise is what the rock is made of. Fervo’s earlier projects went into metamorphic and igneous rock, the hard crystalline stuff (granite is the classic example) that enhanced geothermal usually goes after. Blanford’s reservoir is sedimentary, made up of sandstone, claystone and carbonate layers, and the company says those are easier and cheaper to drill than granite.<\/p>\n

If you’ve ever put a drill through a wooden stud and then hit a concrete wall, you already get the idea. The company’s executives told analysts in August that granite is a much harder rock to drill through than shale, and that a good chunk of their engineering work goes into gear that can survive it.<\/p>\n

Under 11 days for 11,200 feet is quick by Fervo’s own history. Latimer said on the same call that the company’s very first well at Project Red took over 70 days to reach roughly 11,000 feet. That’s not a perfect comparison, admittedly. As far as I can tell, the Nevada well turned and ran sideways for part of its length, which is slower work than going straight down. The crews have also gotten a lot faster since then, and Fervo’s Sawtooth 7 well at Cape Station<\/a> reached 19,448 feet in 21 days this summer.<\/p>\n

Still, a hotter field in softer rock is a pretty nice combination to stumble onto.<\/p>\n

Except Fervo says it didn’t stumble onto it. According to the company’s announcement<\/a>, its AI-driven subsurface analytics picked out the hot sedimentary basin as a new kind of target and helped plan the drilling. Jack Norbeck, Fervo’s co-founder and chief technology officer, said the result shows the team can “detect and develop EGS sweet spots” with AI-assisted geophysics. That’s a fairly corporate way of saying the computer picked a good spot. I’ll give them this one, though, because the first well the computer picked came back hotter than anything else they’ve drilled.<\/p>\n

We still don’t know much about Blanford<\/h2>\n

So when does Blanford start making electricity?<\/p>\n

Nobody outside the company can say yet. Fervo hasn’t put a power figure or a timeline on the site, and I can’t find a customer attached to it. As far as I can tell, there isn’t a horizontal well there yet either. Cottonwood is what the company calls an observation well. It’s a straight hole drilled to measure the rock, and that’s a long way from the sideways production wells that actually feed a power plant.<\/p>\n

Fervo did run what’s called a diagnostic fracture injection test in the well. You pump fluid in until the rock cracks a little, shut the pumps off and watch how fast the pressure bleeds away. That tells engineers how the rock breaks and how tight it is, and Fervo says the test confirmed it can stimulate the formation.<\/p>\n

Then there’s the size. An independent assessment based on the drilling data puts Blanford’s potential at multiple gigawatts, according to Fervo, but the announcement doesn’t name the firm that did it. I’d treat “multi-gigawatt” with some caution anyway. It’s an estimate of heat in the ground, and power plants are a different thing. Fervo says Cape Station has more than 4 gigawatts of total potential, and the company is building 500 megawatts of it.<\/p>\n

Fervo describes Blanford as a cluster north of Cape Station and hasn’t pinned it to a town. Millard County is big, quiet country, with 12,975 people at the 2020 census.<\/p>\n

Which means the next useful information probably won’t come from Blanford at all. Fervo’s second-quarter results<\/a> say the company expects to start a new round of appraisal drilling in the fourth quarter of 2026, and Latimer told analysts on August 12 that it would look a lot like the Blanford campaign, with prospects in Nevada among the first in line.<\/p>\n","protected":false},"excerpt":{"rendered":"

If you’ve read anything about geothermal power in Utah lately, it was probably about Cape Station. That’s the plant in … <\/p>\n

Read more<\/a><\/p>\n","protected":false},"author":8,"featured_media":24492,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[116],"tags":[],"class_list":["post-24493","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-energy","resize-featured-image"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.autonocion.com\/us\/wp-json\/wp\/v2\/posts\/24493","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.autonocion.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.autonocion.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.autonocion.com\/us\/wp-json\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/www.autonocion.com\/us\/wp-json\/wp\/v2\/comments?post=24493"}],"version-history":[{"count":2,"href":"https:\/\/www.autonocion.com\/us\/wp-json\/wp\/v2\/posts\/24493\/revisions"}],"predecessor-version":[{"id":24654,"href":"https:\/\/www.autonocion.com\/us\/wp-json\/wp\/v2\/posts\/24493\/revisions\/24654"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.autonocion.com\/us\/wp-json\/wp\/v2\/media\/24492"}],"wp:attachment":[{"href":"https:\/\/www.autonocion.com\/us\/wp-json\/wp\/v2\/media?parent=24493"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.autonocion.com\/us\/wp-json\/wp\/v2\/categories?post=24493"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.autonocion.com\/us\/wp-json\/wp\/v2\/tags?post=24493"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}