Sir Shelby M. Penwood being a descendent from a noble family was able to inherit wealth and a hight position in British Navy even through on the surface he appears as a somewhat cowardly and incompetent man.
Still Sir Penwood is a long time family friend to Hellsing household, he was a comrade to Arthur Hellsing and kept an eye on Integra after Arthur passed away. Penwood's family wealth is used to cover expenses of Hellsing organisation frequently.