We present preliminary amplification results for DiPOLE, a prototype diode-pumped cryogenic gas cooled Yb:YAG amplifier. Amplification of ns-pulses at 1030 nm has demonstrated output energies of 10.1 J at 1 Hz in a 4-pass extraction geometry and 6.4 J at 10 Hz in a 3-pass setup, corresponding to optical-to-optical conversion efficiencies of 21% and 16%, respectively. Measured performance compares favourably to existing systems and confirms the viability of the concept for efficient generation of high energy pulses at multi-Hz repetition rate. Work is now underway to confirm the scalability of the concept with the design of a 100 J amplifier system. This along with advances in Ti:Sapphire amplifier technology opens the way to the development of a multi-Hz, PW-class laser facility at the Central Laser Facility. Knowledge gained from these developments will de-risk the technology necessary to build a sub-aperture beamlet for a laser driver suitable for fusion energy generation.