Before Ekofisk, there was Groningen. This giant gas field, one of the world’s top 20, revolutionized Europe’s energy industry. But it almost didn’t happen. In a book titled “The Texan and Dutch Gas,” Douglass Stewart, who was working at Esso in 1960, recounts the complex political and regulatory wranglings that were needed to turn natural gas into a fuel source in Europe, going against the coal giants that ruled at the time.

Stewart was informed of a discovery in The Netherlands that Shell was “holding back on” and was sent to Amsterdam to check it out. Since the two companies had a 50:50 partnership in the country called Nederlandse Aardolie Maatschappij (NAM), Esso executives were understandably upset about the lack of sharing.

They had bigger issues facing them. Europe had virtually no natural gas infrastructure, and Stewart described “the challenging negotiations that led to the formation of the northern European gas distribution and marketing organizations of the last 40 years.”

Working with his Shell counterpart, Stewart discovered that Dutch homes were actually fitted for natural gas, called “town gas,” but that it was so expensive that everyone burned coal instead. The two men envisioned an infrastructure that would connect every Dutch home to gas from Groningen. “Although it would take several years to convert all these cities to natural gas, the proven gas reserves were more than sufficient to supply the households and small commercial consumers in The Netherlands,” Stewart wrote. “It was certain the reserves far exceeded what was being speculated at Groningen. The recognition of the untapped market beyond The Netherlands, in Germany and Belgium, kept growing in [my] mind. Dare [we] imagine even beyond?”

The field
As it turned out, daring to imagine was exactly what was needed. Original estimates of recoverable gas were 2.7 Tcm to 2.8 Tcm (95 Tcf to 99 Tcf), according to NAM’s website. As of 2009, on its 50th anniversary, the field had produced 60% of that.

The reservoir lies at about 3,000 m (9,840 ft) and is about 100 m (328 ft) in thickness. It extends over about 900 sq km (347 sq miles) and has about 300 wells spread over 29 production clusters.

Due to the Arab Oil Crisis in 1973, the Dutch government decided to keep Groningen gas in reserve and produce from smaller fields, using Groningen gas only when demand outstrips supply. In addition, the field is used as a gas storage field in the summer, which helps pressure it up for winter production.

Earthquakes
Recently the field has gained notoriety for a series of earthquakes, the strongest measuring 3.6 on the Richter scale, according to Dutch News. According to that source, the quakes are caused by the extraction of natural gas. “The government has been forced to screw back production because of the quakes, which have damaged thousands of homes,” the news source reported. NAM also is being required, by court order, to compensate the homeowners.

This has caused the government to further reduce production in an effort to lower the intensity of the quakes. Production in 2015 has been scaled back to 30 Bcm (1 Tcf).

According to Sander VanRootselaar of NAM, who responds to press queries about the earthquakes, the company is considering various injection strategies to offset the subsidence, including CO2, nitrogen and water. “From these three options, we’re still studying nitrogen,” he said. “There are still technical uncertainties if injection on this scale would reduce earthquakes or cause even more.”