REMVue and SlipStream Retrofits on Gas Compressor Sites
Approved for funding through Round 2: Industrial Energy Efficiency in 2011 , Cenovus implemented two technologies to increase energy efficiency and reduce methane emissions at their gas compressor sites across Alberta. By completion in 2014, numerous air/fuel ratio (AFR) and vent gas capture (VGC) controllers were installed on engines across the province, achieving fuel-gas savings and related greenhouse gas (GHG) benefits.
The project involves installing REMVue AFR controllers onto engines and SlipStream VGC controllers, tying in vent sources into engines and offsetting fuel. The retrofits aim to reduce fuel usage and vented emissions of natural gas from Cenovus’ engine driven gas compression facilities in Alberta. AFR increases fuel efficiency and reduces NOx, N2O, and carbon monoxide. VGC collects and inserts methane rich compressor gases into the fuel system on an AFR controlled engine resulting in CO2 emissions reductions. Both technologies are now commercially available and during the project Cenovus developed improved methods to capture vents, best practices, and economic carbon offset credit learnings.
Better Results on Rich Burn Engines
The project installed REMVue AFR controllers on 11 engines and Slipstream VGC controllers at 28 facilities, tying in over 220 vent sources into engines to be used as fuel. It was discovered that AFR installations on rich-burn engines have greater potential savings and GHG reductions. More energy efficiency gains can be made from the rich to lean conversion than on existing lean burn engines. Fuel savings enabled by VGC are impacted by the size and quality of the vent sources.
Locating the SlipStream near to the vent source is optimal to economically capture the vents. Additional project learnings found that installing this equipment during development rather than retrofitting would have the greatest cost efficiency. It was found that retrofitting applications are most economical on engines and compressors that don’t require upgrades to be able to support the technologies.
What’s next?
Since the project completed, the REMVue and SlipStream technologies have become commercially available and widely used technology. AFR controls were accepted as eligible technology upgrades by ERA’s Small Producers Energy Efficiency Development (SPEED) program, which helped enable broad scale up. The SPEED program provided $15M in funding and facilitated 37 AFR projects, addressing the high demand of companies wanting to install this technology. The program enabled more retrofits and installations, resulting in significant emission reductions and economic benefit. RemVue AFR can achieve fuel gas savings up to 15 per cent and contributed to eight megatonnes of Spartan Control’s accumulative emissions reductions to date. Spartan is progressing with customers to improve the performance of compressor stations’ combustion engines with multiple approaches that are now improving the NOx outcomes and reducing emissions $20 – $30 per tonne.