G

eothermal energy can pro-

vide clean, renewable, basel-

oad electricity, but it has its

challenges. Upfront project costs

are high due to the need to drill and

explore potential sources and, in

some parts of the world, projects

can be subject to lengthy permitting

periods. In the US, for example, it

The technology is also limited by

geography. Geothermal resources

are often located in specic regions

with high geothermal activity, such

as Iceland, Indonesia, the Philip-

pines, and specic locations in the

western United States.

Consequently, uptake has been lim-

ited. According to the International

Energy Agency’s most recent report

nology improvements and reductions

in project costs, geothermal could

meet up to 15 per cent of global

electricity demand growth to 2050.

This would mean the cost-effective

deployment of as much as 800 GW

of geothermal power capacity world-

wide, producing almost 6000 TWh

annually, i.e., equivalent to the cur-

rent electricity demand today of the

US-based company has developed

an innovative system that is bring-

ing geothermal energy to the oil and

gas sector, with the potential to also

power the rapid global expansion of

data centres.

Known as the HXC system, it is

essentially a system that conveys

heat from generally dirty wastewa-

ter sources for use in an organic

Rankine cycle (ORC) for power

generation.

Benjamin Burke, CEO of Geother-

mal Gradient, explained the roots of

being produced and cooling off on

the surface… I realised there was an

opportunity in the thermal side of

water and that’s where the spark for

the company really came from.

“I was one of the company’s co-

founders in 2020. The HXC system

itself came from the need to connect

ORC units to oil and gas facilities…

We needed to convey heat from a

very clean water. That’s where the

idea of the HXC came from.”

The system has two key compo-

nents. One is the HXC sled to con-

vey heat from a produced uid

stream to the ORC. The second sled

is the ORC itself, and Geothermal

Gradient is able to adapt any off-the-

shelf ORC to work with a dry air

cooler.

rural location in the world.”

He notes that the same sled con-

cept can really be used in a number

of ways. The company has in fact

had a good amount of interest from

oil and gas operators all over the

world.

The units are also sized so they

can be installed as small modules,

according to the operator’s needs.

Each sled can produce anything

from 75 kW to 300 kW using differ-

ent sized ORC generators.

“The modularity is what our cli-

means that we can move it on to the

next site.”

he system needs uid at a tem-

perature of at least 70-75°C to oper-

ate, and 2000 barrels/day to make a

reasonable amount of power. “The

more the merrier in terms of both

temperature and uid ow, to get

more power,” noted Burke.

A handful of projects have already

stallation is with an oil and gas op-

erator in the Williston Basin in

western North Dakota. The second

commercial project is due to start

up this month (May) in western

Louisiana.

Burke added: “We’re very excited

to work on a project in Argentina,

which will hopefully be kicking off

later this calendar year, as a well as

different geothermal operators ap-

proach us in the last four months…

Some geothermal operators are op-

erating and drilling, and planning to

have larger facilities. Our equip-

ment can help them to get to rst

electrons very quickly and test

some of their wells. They are look-

ing to use us, while their large more

bespoke multi-megawatt power

ment at liquid-cooled data centres.

These data centres typically have

processors sitting in a bath of water

or some form of refrigerant. This

heat from the processors is pumped

outside the building, usually to a

uid chiller and cooled off.

“Our equipment, in making pow-

er, can act as that uid chiller,” said

Burke. “Additionally, we can use

coming out of it, which to our

equipment looks a lot like an oil

and gas well and we can cool that

uid stream ust as we could cool

an oil and gas well.

According to Burke, the company

has received “a lot of initial excite-

ment” over the idea of a water-free

solution for data centre cooling. This

is important since many of the exist-

ing cooling solutions for water-

cooled data centres involve some

type of misting, or evaporative cool-

ing, which can be a problem in parts

of the world where water is scarce.

According to Burke, the econom-

ics of the technology also stack up

sel installations.

Geothermal Gradient has initially

adopted a lease model for HXC,

which is well suited to the modulari-

ty of the system.

Burke noted: “Although we cer-

tainly can sell the units, we’ve start-

ed as a leasing model because a lot

of oil and gas operators tend not to

own the heavy equipment that they

HXC cost competitive with existing

solutions. “In leasing these units,

[compared to] the incumbent solu-

tion that we are replacing, we are es-

sentially one-to-one or slightly less

expensive than the amortisation cost

of the uid chillers that operators

currently use,” said Burke. “Plus,

they get power [from the HXC sys-

tem], as opposed to pulling power

He explained that a one-off solu-

tion for a client is not the most cost-

effective option but noted: “At a full

build-out we’re on the order of 8-11

cents/kWh, when power generation

is the goal.” Burke added: “If heat

rejection is the goal – for a lot of our

clients, uid chilling is the primary

goal – whatever they get from that is

secondary. So there, you have to

As long as water is owing, day or

night HXC can make power and pro-

vide cooling duty. With a capacity

factor above 90 per cent, this com-

pares very favourably with solar at

20-25 per cent or wind at 30-40 per

cent. “When this capacity factor is

normalised against the levelised cost

of energy, we’re as cheap as wind

and solar, if not more so,” said

duced every day and have that

advantage work for our clients, work

for ourselves, and in some cases

work for public entities where the

wells are in the public domain. It’s

been gratifying to see that interest

truly worldwide in the uptake of our

technology.”