The UK once hoped for an American-style fracking boom. It's not happening

London(CNN Business) The United Kingdom once hoped that fracking would unlock its shale energy reserves, enhancing the country's energy security and creating jobs and new tax revenues in the process. That now looks unlikely to ever happen.

Only three wells have been fracked in the country to date, according to a report this week from the National Audit Office (NAO), which monitors government spending. The UK government had been hoping for 20 wells by the middle of 2020.

The NAO cites multiple factors for the slow start: Public support for fracking was weak to begin with and has dropped over time. The size of UK shale reserves remains unknown and the cost effectiveness of extraction has not been studied by the government.

Even more dramatic, each of the three wells have caused earthquakes more powerful than the 0.5 magnitude threshold that requires a pause in operations, according to the NAO. The most recent was a 2.9 magnitude quake in August.

Fracking, which unlocks natural gas and oil, involves injecting a mixture of water, sand and chemicals at high pressure into a well. It has sparked protests and public concern because of the threat it poses to groundwater and wildlife.

According to the NAO, the government still believes fracking could help the economy. But as public pressure builds for more urgent action to tackle the climate crisis, fracking in the United Kingdom looks doomed unless new technologies to capture carbon emissions from burning shale gas can be developed fast.

Meanwhile, in America

Widespread fracking has in recent years transformed the US energy industry, driving oil production higher while creating high-paying jobs.

In 2016, fracking accounted for more than two-thirds of all oil and natural gas wells drilled in the United States, according to the US Energy Information Administration.

Even more noteworthy has been the disruption to the balance of power in global oil markets.

US oil production has more than doubled over the past decade to about 12 million barrels per day. The United States briefly overtook Saudi Arabia and Russia as the world top oil exporter in June, according to the International Energy Agency.

Eclipsed by renewables?

The nascent UK fracking industry pales in comparison to that of the United States.

Cuadrilla, the only company that has fracked for shale gas in the United Kingdom, was forced to suspend operations at one of its wells in Lancashire, England, following the earthquake in August. But the firm is sticking to its guns and testing another shale gas well.

"We are committed to exploring for shale gas with the aim to establish a domestic energy supply that the United Kingdom really needs," CEO Francis Egan said in an emailed statement.

Producing natural gas locally from UK shale was preferable to "ever increasing gas imports," he added.

The UK's Department for Business, Energy and Industrial Strategy told CNN Business that it would set out its future approach to fracking once it had considered the findings of an imminent industry assessment by the Oil and Gas Authority, a government agency that regulates oil and gas resources.

In addition to environmental concerns, the fracking industry faces another big challenge: the cost of renewable energy is falling fast.

The UK government wants the country to become a global leader in renewables and plans to derive a third of its electricity from offshore wind by 2030. For fracking, the game may already be up.

— CNN Business' Matt Egan contributed to this report.