LONDON, Feb 7 (Reuters) - British Prime Minister Rishi Sunak reshuffled his cabinet on Tuesday, breaking up two departments to better suit his pledges to spur the economy, reduce energy prices and turn around his party's fortunes before an election expected next year.

Sunak created a new energy security and net zero department, led by former business minister Grant Shapps, and three other departments, with one focusing on science and innovation, a personal passion for the British leader.

The former finance minister and multi-millionaire, who once worked for a hedge fund, is trying to steer the economy through a prolonged period of double-digit inflation and stagnation, a situation worsened by the soaring cost of energy.

He is also under pressure to try to prove his belief that Britain can reap the benefits of its departure from the European Union by developing new trade ties with international partners.

"The government needs to reflect the priorities of the British people and be designed to deliver for them," Sunak said on Twitter. "These changes will focus teams on the issues that will build a better future for our children and grandchildren."

He hailed the standalone energy and net zero ministry as one that would help Britain gain greater energy security and start producing cheaper, cleaner energy to avoid the kind of price hikes people had to pay after Russia's invasion of Ukraine.

His spokesperson said the changes, which were welcomed and criticised in equal measure by business groups and green energy supporters, might not offer a "silver bullet" to all Britain's ills, but would help Sunak try to deliver on his agenda.

In the changes, trade Secretary Kemi Badenoch was given an expanded role including business and trade.

Former culture minister Michelle Donelan was appointed to run the department for science, innovation and technology, while former housing minister Lucy Frazer took on the new role for culture, media and sport.

Greg Hands, a former trade minister and one-time party enforcer for the Conservatives, was appointed party chair.