After a short rest, William and the others moved on. Following the computer's instructions, they went to the next location. A few kilometers from his destination, William's sharp eyes spotted an innumerable number of tall white objects standing in the distance. They seemed to be spinning. As they got closer, he realized that those objects were wind turbines. Compared with these "giants", they were as small as ants in front of men or Earth in front of Sun.

A robot approached them. "Hello! You must be William." Said the robot.

"Yes, but how do you know who we are?" He replied in surprise.

"Thanks to your little robots!" Laughed the robot, "They don't frequently go out of your backpack these days, do they?"

"No."

"My guess was correct. They've been hiding in your backpack searching for other robots nearby that can communicate!"

"Really?" William asked, pulling out a small robot. It nodded.

"That's great! I had no idea you were so capable. I thought you'd been taking breaks to cut down on electricity consumption!" William was overjoyed.

"Let's go and meet an engineer. He's waiting for you." The robot led the party across the wide plain. The light of the two mother stars twinkled, illuminating the planet. Wind turbines span slowly beneath the high canopy, silently powering the planet. As the wind picked up, their blades span faster, their tips drawing perfect arcs in the air.

Before the grass had time to enjoy the warm light, large clouds gathered in the distance. Thunder rolled as if a giant sluice gate were about to open next second.

"How far are we to get there?" William asked the robot, looking worriedly at the gloomy sky.

"In two minutes! This wind farm is huge, but we are taking shortcuts. You see, the blue villa in front is it." They succeeded in getting into the engineer's room before the rainstorm came.

The engineer was already waiting beside the door. "Nice to meet you!" He ushered the party through the door. "Your robot did a great job, Sir." Ranran joked, "If he hadn't taken us on a shortcut, we would have gotten wet."

"Ha ha! That's true." Said the engineer, looking out of the window at the rainstorm. He saw William looking in the direction of the wind turbines and comforted him, "It'll be all right. Our windmills can withstand even a 5S earthquake and a KK typhoon, not to mention the fact that the planet is not geologically active."

Natalie figured out that this was the equivalent of a magnitude 11 earthquake and a magnitude 14 typhoon on Earth.

"Your robot says the wind farm is huge, but we just took a shortcut and couldn't see it. I'm a little sorry." William said.

The engineer said, "Never mind! My robot doesn't lie, ha ha. At the rate you were going, it's going to take you at least 20 minutes to get all the way across the wind farm. We use windmills with a power of 15 megawatts per unit, with a total installed power of about 30 terawatts. That's enough to supply 30% of the planet's electricity."

"Wow, this wind farm is really spectacular and useful!" Exclaimed Ranran, "But how is the other 70% of the electricity supplied?"

"Only about 5% of our electricity is supplied by thermal power, and we use relatively low carbon fuels. So the pollution and greenhouse effect can be ignored. 50% is generated by fusion and the remaining 15% is by fission. It looks like 80% of the electricity supply is clean. So if you spend any time on this planet for a long time, you will find that the environment is absolutely excellent."

"That's another day, too." William said, "We're on a mission, so we can't spend too much time on this planet. I let you down."

"It doesn't matter. Since you have a mission, I want to treat you well, lest you just come from far away and be too tired."

"Er... Actually, we just had a break, at a mushroom pianist."

"A mushroom pianist? Is it the one who lives in the log cabin, plays the piano very well and let you sleep in the big room underground?"

"Yes, that's him!" Cried Photon excitedly, "You know him too?"

"Of course I do," Said the engineer confidently, thumping his chest, "because we both know the camel scientist, and the mushroom's house is powered by fusion and my wind farm. So we know each other. Didn't he introduce me to you?"

"No." Natalie replied, "It's just that he gave us a good rest. We have a map which indicates that we should come here. And the mushroom pianist showed me directions before we left. It is right here."

"Oh, I see. But I'm curious about what you mean by your mission."

"They're going to help me train." Rebecca replied, "I'm going to the flying endurance race."

The engineer looked at Rebecca carefully. It was about half a minute before he knew it and said, "Oh! You're Rebecca, the former champion!"

"Yes, it is me. You flatter me." Replied Rebecca modestly, "But I never heard of you, Sir. Maybe it's because I don't come here very often to train. The race is still at the same place, but this time I took a new route. That's why I met you."

"I'm an old fan of yours, Rebecca. I wish you success in the race!"

"Thank you very much!"

"Sir, why are your windmills so high-power? I remember seeing a similar size windmill that had merely 10 megawatts." William asked.

"That's because the materials inside them have excellent properties." Replied the engineer, "The blades are still made of carbon fiber and have a more hydrodynamic profile, which allows them to capture wind energy more efficiently. The breakthrough is in the generator section. I considered what kind of metal-containing superconductors would be used for the stator coils of the generators, but now, thanks to new research by the camel scientist, the coils are made of a conductive polymer, a polymer that is more conductive than even the best superconductors of the past. Also, It is much easier to maintain its high conductivity. Coils made from it can withstand higher voltages and stronger currents, thus guaranteeing greater power."

"What a great contribution the camel scientist has made!" William was filled with admiration.

"When we tried to make coils out of conductive polymers, they worked very well." Said the engineer, "This time the camel scientist found some better additives, so the performance took another leap forward." Then he looked out of the window. The rain had stopped, but the sky was still overcast. So he stood up and suggested, "Well, it's not raining now. If you want to see the windmills, come with me."

The party cheered and followed the engineer out of his villa. Although the clouds had not cleared, the rain would not come again for a while. After the rainstorm, the low grass on the plain was glistening with water. Wind turbines waved through the air with three huge, stout arms and sweated silently to power the planet. The white giants stood in neat rows. Seen from the air, it was simply a beautiful picture.

"Only you and your robot manage a this big wind farm? Aren't you working too hard?" Ranran asked.

"Certainly not. These are smart devices that are not complicated to maintain." The engineer replied.

Photon looked up at these giants. "Look at this." He said to Natalie, "Even though Earth is very clean now, I think the environmental awareness here was formed long before that on Earth was."

"You're right." Natalie replied, "We didn't have large-scale fusion until around the year 2080. I would expect it to happen at least 30 years earlier here."

"Everybody, since you have come to such a magical and rare place, why don't you take a picture?" William suggested. So they quickly arranged their place. One of William's small robots adjusted their places and took pictures, and this memorable moment was captured in this way.

Ranran was breathing the moist and fresh air and smiling. The graceful arcs of the tips of wind turbines set off her delighted face. A strong wind blowing, Ranran's long hair was flying, while the grass on the ground had to bend. But then the wind died down and they began to dance happily.

They lay on the grass and looked at the dark but brighter sky. William said to the engineer, "What you don't know, Sir, is that it was not until 70 years ago that we were able to enjoy such a beautiful environment on my planet. We had a bad environment for more than a century before that, and then it gradually improved with greater awareness."

"Really? It happened here a century ago. In fact, we were in the harsh environment you described, and the situation may not be any more optimistic than yours. But we had a relatively short time and found the 'green solution' very quickly."

"That's nice. Before, we were too greedy. We only cared about building the economy yet ignored environment protecting. That more than a century of harsh environment was a painful lesson. Fortunately, we improved in time, or we might even have to move to another planet."

"That's really lucky. Moving to another planet is not a easy task."

The party lay comfortably on the ground like this, letting the breeze blow by. William, who was the happiest of all, knew that the rest of the journey would probably never be as easy as it was now. He did not know how many unknown obstacles were waiting for him, so taking a good rest first must have been a wise choice.