NIGRAN, SPAIN, Mar 7 (Reuters) - Spanish space company Sateliot is raising funds to put 100 microwave oven-sized satellites into orbit, entering a tight race to grab a slice of a potentially $100 billion market for offering cheap data connections through space.

The company, which already has two test satellites in orbit, is seeking 100 million euros ($109 million) in equity and debt from private equity investors, funds and banks, CEO Jaume Sanpera said in remarks cleared for publication Thursday.

Sateliot expects to launch its first four commercial satellites in June.

Sanpera told Reuters that "with just four satellites" they could bill and have commercial activity in the second half of 2024, at Sateliot's facilities (in northwestern Spain), where its teams manufacture the nanosatellites.

Sateliot has an order backlog of about 187 million euros in annual revenues, and its customers are mostly from countries with vast areas not covered by mobile networks, such as Canada, Brazil, South Africa, Indonesia or Australia, Sanpera explained.

Sateliot has spent some 25 million euros to develop, build and put into orbit, through SpaceX, the two test satellites and the first four commercial satellites.

The space industry is undergoing a market revolution as new technologies have reduced the cost and size of space devices to a fraction of what they used to be, and many start-ups have joined the fray.

Lucas Bishop of investment firm Seraphim Space says only the most profitable of the few dozen nanosatellite operators will make it.

While the big operators, such as Elon Musk's Starlink, are focused on providing high-speed Internet connectivity on the ground from a network of thousands of satellites, new companies are creating smaller networks, called constellations, to extend the reach of the "Internet of Things," also known as IoT.

Sateliot's goal is to connect small devices, such as control equipment for refrigerated containers transported by sea, via satellite. Potential customers include logistics companies, farmers, oil rigs or environmental applications, according to Sanpera.

Luigi Scatteia, space consultant at PwC, said the ability to operate and maintain the entire system seamlessly, including robust, autonomous and low-power equipment at the user end, with advanced software, is another key challenge, possibly more complex than deploying the satellites.

Sateliot, owned by defense contractor Indra, telecom infrastructure operator Cellnex and the Spanish state for 10.5%, 3.5% and 4.69%, respectively, expects to deploy all 100 satellites by 2028 and turn over €1 billion by 2030.

(1 dollar = 0.9196 euros)

(Reporting by Inti Landauro and Miguel Vidal; editing by Andrei Khalip and Tomasz Janowski; Spanish editing by Javi West Larrañaga)