“They are widely recognized as the world's leading solar energy company.”

You're writing a report about a company. It is #1 among companies of their type. You are introducing the company at the beginning of your report, and write:

They are widely recognized as the world's leading solar energy company.

widely recognized as (something)

When many people agree that a company is the best, you say the company is "recognized as" the best. Similarly, if you are "recognized as" one of the best athletes at your school, it means that a lot of the people at the school agree that you are one of the best.

If most people agree about a description, you can say something is "widely recognized as" being that way. "Widely recognized" means recognized by a large number of people.

the (world/nation/industry/etc.)'s leading (something)

The #1 person or thing in a group is called "the leading ___". This is often used with job titles and professions:

• the world's leading doctor
• New York's leading personal trainer

You can also use this expression to talk about companies, products, etc:

They are the industry's leading seller.

We are the East Coast's leading provider of audio-visual equipment.

solar energy

"Solar energy" is electricity that's made from the sun using solar panels.