(Reuters) - General Electric Co (>> General Electric Company) Chief Executive Officer Jeff Immelt is sticking by his company's model for housing diverse businesses under one roof at a time when other U.S. conglomerates are looking at hiving off units to please investors.

In a wide-ranging annual letter to shareholders released on Monday, Immelt details advantages from such scale through shared technology and other areas through what he calls the "GE Store."

"The value of the GE Store is captured by faster growth at higher margins; it makes the totality of GE more competitive than the parts," Immelt writes.

As an example, Immelt cites how GE can use aircraft engine alternators to improve motors for pumping oil. He points to additive manufacturing, also known as 3-D printing, as a new technology for potential use across GE's businesses, which include power turbines, locomotives and MRI machines.

Immelt's comments follow GE's meeting last week to showcase its technology to investors, in what some analysts also viewed as providing rationale for a conglomerate model.

They also come after rival U.S. conglomerate United Technologies Corp (>> United Technologies Corporation) last week announced it would weigh a spinoff of its Sikorsky helicopter unit after a portfolio review. Other industrial companies, such as Tyco International Plc (>> Tyco International PLC) and ITT Corp (>> ITT Corp), have undergone more significant breakups in recent years.

To be sure, Immelt has gotten GE out of businesses such as plastics, and last year decided to sell its appliances unit as it reshapes its industrial focus. It is also scaling back its finance division.

Barclays analyst Scott Davis has in the past raised the prospect that investors want GE to go further, including shedding its medical business.

Immelt writes in the letter that two of GE's newest products - its LEAP jet engine and H-class gas turbine - will generate $100 billion in combined revenue over their lives. He also says GE will register at least $1 billion in sales in Ghana this year, joining 22 other countries.

While GE has warned sales in its oil segment could fall 5 percent this year amid the slide in oil prices, the CEO writes in the letter that the price drop presents an "opportunity" for the business, which supplies equipment and services to energy customers.

"The oil and gas industry should be able to compete at current oil pricing," Immelt said. "GE will lead."

(Editing by Jonathan Oatis)

By Lewis Krauskopf