The new 120,000 sq ft depot has been strategically positioned close to the Thames Crossing and M25 to cover Greater London and the South East of England.
The investment is part of a £7m nationwide fleet investment.
At Erith 15 new jobs have been created, 10 of which are new engineer roles.
In addition to some of the newest and most efficient generators on the market, such as the SDMO Power Generators and Doosan 7/13G Compressors, the Erith depot will also house 20, 24/7 call out engineers as well as an on-site workshop.
Five specialist staff have been hired for individual and dedicated pumps, compressors and generator hire desks.
The new Erith power depot replaces Speedy’s previous London power depot in Charlton.
Len Clough, Erith General Manager, said: “Our customers play a crucial role on many large and time sensitive projects across the region making the provision of the latest power equipment and round-the-clock support services essential.
“The new depot at Erith is part of a nationwide investment programme designed at improving the support we provide our customers through expanding our fleet, reach and range of services.
“The relocation to the improved site has enabled the expansion of the on-site fleet holdings, service engineers and fuel management services, enhancing our response times and capabilities to our customers in the region.”