In support of our greenhouse gas (GHG) emission and flaring intensity reduction targets, we track and monitor air emissions at each of our assets and undertake a variety of emission reduction initiatives.
Our efforts focus on our largest emitting facilities and on opportunities that are technically and economically feasible and where we are able to achieve stakeholder approval. In 2016 reduced oil and natural gas production related to weaker-than-anticipated energy demand, as well as the continued low price of oil, reduced the pool of emission reduction opportunities.
The following case studies supplement those found in our 2016 Sustainability Report.
Bi-Fuel Rigs and Boiler Conversions
In North Dakota we have worked with our contractors to convert diesel engines to bi-fuel natural gas/diesel engines on several drilling rigs operating for Hess in the Bakken. The bi-fuel engines use natural gas captured at the wellhead. They reduce air emissions by using cleaner-burning natural gas rather than diesel to fuel the rigs, reducing emissions associated with diesel fuel truck deliveries and reducing flaring. The conversion also results in reduced fuel costs. Also in North Dakota, we utilize nine boilers that have been converted to operate exclusively on natural gas during winter operations. In 2016 the converted rigs and boilers saved 766,000 gallons of diesel fuel, reduced GHG emissions by an estimated 2,200 tonnes and resulted in 100 fewer truck deliveries.
We began piloting power generation utilizing gas from our Bakken operations in 2014 and, building on that experience, implemented gas generation at a second site in May 2016. As part of this project we replaced eight diesel-powered generators with 170 kilowatt gas-fueled generators. We use 270 thousand standard cubic feet per day (MSCFD) of gas from these sites, displacing diesel fuel, to directly power the sites’ electrical needs. In 2016 these generators eliminated 13,410 barrels of diesel fuel use and reduced GHG emissions by 1,600 tonnes. In 2017 a third site will be added that will help decrease GHG emissions by another estimated 800 tonnes per year.