Chen Hao stared at the temperature curve on the screen. The red line jumped again, to 79.3, and then fell back down. He blinked, thinking he had misread it.
"Did it move again just now?" He reached out to touch the mouse, but Nana stopped him as soon as his hand touched it.
"Hands weren't clean," she said. "The contamination level was too high."
"I already said it wasn't intentional." He withdrew his hand, took out a wet wipe from his pocket, and wiped it rather carelessly. "I just bumped into a drilling rig, how dirty could it be?"
Nana ignored him and pulled up the millisecond-level recording graph. Zooming in, a tiny peak clearly appeared, lasting less than two seconds.
“There is fluctuation,” she said. “The amplitude is 0.8 degrees Celsius, and the source is unknown.”
Chen Hao leaned closer to look, his nose almost touching the screen. "Is it alive down there? It's like it's breathing."
“Geothermal activity is periodic,” Nana said, “but this fluctuation frequency is abnormal and requires further observation.”
"Does that mean it will come again?"
"The probability is relatively high."
Chen Hao leaned back in his chair, which made a dull thud. "Fine, we don't have anything else to do anyway. We've already dug it up, we can't just cover it up and pretend we didn't see it."
He sat up straight and slapped his thigh. "Let's get started. How do you suggest we do it? Just connect a pipe and pump the hot water up?"
“It’s not feasible.” Nana projected a cross-sectional diagram. “The groundwater contains sulfides and weak acids. Ordinary metal pipes will corrode and perforate within seventy-two hours.”
"What about plastic?"
"Insufficient pressure resistance; it will soften and deform if the temperature exceeds 60 degrees Celsius."
Chen Hao scratched his head, "So we have a heat source, but we can't use it?"
“A closed-loop heat exchange system is needed.” She pulled up a set of structural diagrams. “Use double-layer stainless steel pipes with a ceramic coating on the inner wall, inert gas insulation in the middle, and connect an external circulation pump to extract energy through indirect heat conduction.”
Chen Hao looked at the picture, his mouth slowly widening into a grin. "Isn't this just a giant thermos?"
"The principle is similar."
“I like it.” He stood up and stretched. “The more complex something is, the more it resembles an everyday item when you take it apart. What about the materials? Do we have any of that stuff in our warehouse?”
Nana began searching the inventory. A list of obsolete equipment scrolled across the screen.
“The titanium alloy lining of the medical module can replace some of the stainless steel components,” she said. “The solar pump assembly can be modified into a pressurization device. The sealing rings can be replaced with spacesuit joint pads.”
Chen Hao's eyes lit up. "You picked them all out of the junkyard?"
"yes."
“Then we’re not building a heating system, we’re building Lego,” he laughed. “And it’s a high-end recycled version.”
The two immediately began compiling a materials list. Chen Hao rummaged through his toolbox, while Nana adjusted the parameter model. Two hours later, the drawings were finalized, and the pipeline layout was completed. The first section of the main pipeline was designed to be twelve meters long, with three bends, connecting the geothermal well to the heat exchange box on the north side of the main control room.
"Work starts tomorrow." Chen Hao yawned. "Let me get a good night's sleep tonight so I'll have the strength to move iron pipes tomorrow."
"The ground in the construction area has softened in some areas," Nana warned. "The steam is erupting intermittently, making the working environment unstable."
"What else can we do? Just wait for it to cool down on its own?"
“We can artificially freeze the soil layer.” She pulled up a new plan: “Bury hollow tubes around the borehole and inject low-temperature liquid to form a ring-shaped freezing zone to stabilize the structure.”
"Sounds like a refrigerator cooling system." Chen Hao nodded. "Okay, let's do it this way. You're in charge of freezing the ground, and I'll be in charge of welding the pipes."
The next morning, the two arrived at the construction site in the southwest corner. The wooden sign on the ground was still nailed on, and the words "Geothermal Well No. 1" were yellowed and curled at the edges by the steam.
Chen Hao squatted down to examine the edge of the borehole and reached out to probe it. "No steam coming out today."
“The pressure is in a state of equilibrium,” Nana said, “but it could be released at any time.”
She directed the robotic arm to begin the pipe-laying operation. Six hollow metal pipes were inserted into the ground in a ring, connecting to a small refrigeration unit. After starting up, a thin layer of frost gradually formed on the ground.
"The cooling effect is effective," she said. "A stable frozen layer is expected to form in four hours."
Chen Hao didn't sit idle; he started assembling the blowout shield. It was made from a salvaged ventilation duct, with a pressure relief vent at the top and a curved exhaust pipe leading to the upper atmosphere.
"If it explodes down there, at least don't spray it in my face," he said while tightening the screws.
By noon, the freezing process was complete. The soil was as hard as stone. Nana confirmed the data met the requirements and allowed the process to proceed to the next stage.
With his modified robotic arm, Chen Hao began welding the main pipeline. The first section consisted of a titanium alloy inner tube, an outer ceramic-coated steel pipe, and the interlayer required vacuuming followed by nitrogen filling.
"This is even more meticulous than cooking," he muttered as he worked, "layer upon layer, as if afraid of letting any air out."
Sparks flew from the welding torch. The first section of pipe was connected, and an airtightness test was performed. The pressure gauge needle remained steadily in the safe zone.
"Passed." Chen Hao breathed a sigh of relief.
There was a problem with the connection in the second section. The interface wasn't aligned properly, and it failed to connect after three attempts.
"Is it crooked?" He measured it with a ruler.
“The support frame has sagged slightly,” Nana said. “The frozen layer has begun to thaw due to the sunlight.”
"Then freeze it again."
They paused operations and replenished the refrigerant. Twenty minutes later, after recalibrating the position, they finally completed the docking.
The third section was the most difficult, requiring passage through a narrow tunnel while avoiding underground cables. Chen Hao lay prone on the ground, holding a welding torch in one hand and a pipe in the other, his movements as slow as if he were moving building blocks.
"If I were ten years younger... oh no, if I were twenty pounds thinner, I definitely wouldn't have to go through all this trouble."
“Body size does not affect technical precision,” Nana said. “It only affects energy consumption.”
"You're really honest."
With the last section connected, the entire pipeline was complete. Nana started the vacuum pump to begin evacuating the interlayer air. The screen displayed the progress: 97%...98%...99%...Complete.
“Sealing achieved,” she said. “Ready to connect to the circulation system.”
At 3 p.m., all the hardware was installed. They returned to the main control room to prepare for the first thermal energy introduction test.
Nana activated the valve control program. Chen Hao sat beside her, holding a pen and tapping it on the table.
"Come on, let's see if this underground hot water is willing to work."
The system starts. The water pump operates, and the circulating fluid begins to flow. Temperature sensor data shows that the temperature of the outer wall of the pipe is slowly rising.
Five minutes later, the heat exchange box began to heat up.
"There's a response!" Chen Hao leaned closer to the monitor screen. "What's the flow rate?"
“One liter per minute,” Nana said. “Lower than expected.”
Why is it so slow?
She brought up the fluid model and found that the resistance at the bend in the pipe was too high, causing the water to flow poorly.
"Route optimization suggestion: Reduce two curves and activate the backup booster pump."
"Wouldn't that mean we have to dismantle two sections of the pipe?"
"yes."
Chen Hao sighed. "Can't we just do it once and for all?"
“There will always be problems the first time,” Nana said. “Otherwise, it wouldn’t be a test.”
They decided to make the changes that very night. Chen Hao was in charge of disassembly and assembly, while Nana remotely controlled the robotic arm to assist. The new three-section pipeline adopted a straight layout, retaining only one necessary bend. The booster pump was connected to the main line, and its power was adjusted to 70%.
The second test began at 8 p.m.
The water flow rate was increased to 1.8 liters per minute. Heat exchange efficiency was significantly improved. The thermometer in the main control room showed that the indoor temperature rose by three degrees Celsius within one hour.
"Not bad," Chen Hao said, rubbing his hands together. "It's getting warmer."
“Continue monitoring,” Nana said. “Prioritize heating for living areas and planting sheds.”
Chen Hao manually adjusted the valves in each room. He first turned the valves in the main control room and dormitory to the maximum, then the kitchen, and finally the warehouse and maintenance room.
Two hours later, the temperature in the main control room rose by six degrees, reaching eighteen degrees Celsius. The humidity in the planting shed returned, and the plant leaves regained their luster.
"It's done." Chen Hao slumped in his chair. "This is legitimate use of natural energy. Boiling water underground and heating the ground, it's environmentally friendly and saves money."
“The system still has the problem of high energy consumption,” Nana said. “The power consumption of the booster pump exceeds the budget by 23 percent.”
"As long as it can warm the house, that's fine." He waved his hand. "We'll talk about saving electricity tomorrow."
He leaned back in his chair, his eyes almost closed. Nana was synchronizing and backing up data, setting up a nighttime inspection program that would automatically record temperature, pressure, and flow rate every half hour.
"We will conduct a second probe deployment at 6:00 AM tomorrow, to verify long-term stability," she said.
"Okay," Chen Hao mumbled in response, still half asleep.
Just as he was about to fall asleep, the control panel screen suddenly flickered.
The temperature curve jumped again.
79.5.
There was no pullback this time.
Nana's camera pans to the screen.
Chen Hao opened one eye.
"It's here again?"
Continue read on readnovelmtl.com