We present the development of a fiber-based high-efficiency laser amplifier (HELA) as a demonstrator for future high throughput satellite communication systems operating in the 1µm wavelength range. The work is conducted in the context of ESA’s ARTES ScyLight framework programme (SeCure and Laser Communication Technology) and more specifically within its HydRON project. Combining the experiences of in-house manufactured optical fiber components and of laser developments for space applications, an all-fiber amplifier solution was designed. The realized laboratory testbed simultaneously amplifies a 10-channel seed input from the mW-level up to a total output power of 100W. Leveraging the benefits of advanced fiber technology, an enhanced wall-plug efficiency of about 29\% has been achieved.