May 16 (Reuters) - U.S. energy company DTE Energy Co said on Tuesday it will build more natural gas and renewable power plants and shut all of its coal units by 2040, reducing carbon emissions by more than 80 percent from 2005 levels by 2050.

“We have concluded that not only is the 80 percent reduction goal achievable – it is achievable in a way that keeps Michigan's power affordable and reliable," DTE's chairman and chief executive officer, Gerry Anderson, said in a statement.

Detroit-based DTE said its efforts to cut carbon emissions will result in a 30 percent reduction by the early 2020s, 45 percent by 2030, 75 percent by 2040 and more than 80 percent by 2050.

The company said it will achieve these reductions by adding more renewable energy, transitioning its 24/7 power sources from coal to gas and continuing to operate its zero-emission Fermi 2 nuclear power plant.

DTE said it would retire its last two Michigan coal plants, the 1,270-megawatt Belle River in 2030 and the 3,066-MW Monroe in 2040.

One megawatt can power about 1,000 homes.

Last year, the company announced it would retire its River Rouge, St. Clair and Trenton coal plants by 2023.

DTE said it plans to build an additional 6,000 MW of renewable energy capacity – enough to supply nearly 2 million homes – supplementing the 1,000 MW of renewable energy it has built since 2009.

The company also said it plans to add 3,500 MW of gas-fired energy capacity.

The combination of all of these actions will enable DTE to produce over three-quarters of its power from renewable energy and gas-fired power plants.

"Like all big transformations, this one won't happen overnight. It needs to be planned carefully and will entail big investments, but that can absolutely be done," Anderson said.

In addition, DTE plans to invest $5 billion over the next five years to modernize its electric and gas infrastructure, which should support more than 10,000 Michigan jobs.

(Reporting by Scott DiSavino; Editing by Leslie Adler)