July 17th, 2024
Written By: Richard Xu
Hello! Richard here, your favorite Sales/Marketing intern here again this summer at Nikira Labs.
Today, I’m blogging to detail my findings with Nikira’s Portable Methane Analyzer or PMA.
On June 26th, I got to take the PMA out on an environmental date for a long adventure, then graphically visualize the experience!
The main goal of my expedition was to measure methane emissions coming from active and plugged but abandoned oil & gas wells around the Bay Area. Using the California Department of Conservation’s Well Finder map application, the Nikira team and I were able to pinpoint two locations where I could potentially get close enough to measure CH₄ emissions.
One of the selected locations was a cluster of oil & gas wells, mostly plugged, but some still active, in the fields of Halfmoon Bay, just off of the highway. The other location was a group of plugged oil & gas wells in the neighboring mountainous area of La Honda.
It is important to note that despite the selected wells being publicly shown on Well Finder, these wells are mostly on private property; hence, our attempt to find wells located as close to public roads as possible was to enable the potential CH₄ emissions measurements without trespassing.
Exploring Half Moon Bay
Upon reaching the first spot near the entrance of Purissima Creek Road in Halfmoon Bay, I parked my car on the side of the road and began to set up the PMA. Set up was a 3-minute breeze: simply attach the shoulder strap clips to the corresponding rings on the PMA, screw on the GPS dongle, click-in the quick-connect filter inlet, and press the power button! With the PMA on and humming, I interfaced my cell phone wirelessly to it in order to conveniently view the real-time CH₄ analysis while on the move; then, I began to take my little stroll down the road.
Over the course of an hour, I tried a number of methods to get an elevated CH₄ reading from the ambient air. I walked back and forth, up and down the road to see if I could get any major CH₄ spikes, to no avail. Then, I decided to get in my car and started driving the same route with the analyzer running and all my car windows rolled down. Unfortunately, what I was visibly detecting was nothing more than just noise.
The oil & gas wells, though visible, were too far from the main road. Here, I need to emphasize the need for two conditions to be met for the PMA to detect a methane leak: an elevated CH₄ concentration (above background levels) and the presence of the PMA downwind from this CH₄ leak. No matter how much I waited, the wind direction would not change from blowing the CH₄ emissions away from me and the PMA.
Eventually, I decided to cut my losses and head back to home base at Nikira Labs’. I truly thought that this run was a dud; however, upon returning to the office, I plotted and analyzed the heat map of the data collected. To my surprise, some subtle, but interesting observations could be made.
Though very small, with the changes being in the hundredths of ppm, the analyzer found spots where the methane levels were 0.03ppm higher (ppm = parts per million).
How do we know this isn’t just noise? It’s because the elevation in concentration is consistent among the same area for many instances, and if we overlap with the Well Finder map we find that the area would just be downwind of an active well that I had forgotten about.
Yet, this evidence of the PMA’s compelling sensitivity is further affirmed with the next measurement trial that I am so excited to talk about.
Driving back to Nikira Labs through La Honda
On the second trial of the PMA, I decided to keep the PMA running in the car during the long drive back to Mountain View in an attempt to explore if the analyzer would detect anything interesting along the way. With all my windows once again rolled down bringing about a nice, cool breeze and the analyzer running, I started my drive back to the office from Half Moon Bay.
I cut through La Honda, to see if the PMA would detect CH₄ readings from any of the passing wells. Unfortunately, these too were all stuck behind private, locked gates making them inaccessible and too far to get good readings from. Leaving the PMA running, I continued driving on the road until I eventually reached the main highway heading back to the office.
At first, since there were no major blips indicative of a methane leak, I thought that the drive had been uneventful, methane-wise, and thus, the entire day was void of interesting metrics. However, once comfortably seated at my air conditioned desk in the office, I plotted out the data via a heat map, and low and behold, the results were quite insightful.
The gradient of colors due to the differences in the hundredths displays the salient sensitivity of
the PMA. The 2 decimals of ppm start relatively low in Halfmoon Bay, a relatively quiet, rural town with slight urban developments, and continue through La Honda. Once out of the mountainous forestry of La Honda, there is the car-filled Highway 280 which merges onto route 85 leading right into the dense urban development that is the City of Mountain View (the home of Google). The heatmap plot gradient reflects exactly this transition: my continuous CH₄ measurement journey starting with low ambient CH₄ concentrations in lush green rural areas and gradually increasing (albeit ever so slightly!) as I approach the car traffic-ridden urban areas.
Both the Half Moon Bay measurements and the drive back through La Honda are clear testaments of the PMA’s imposing capability to detect even the most subtle differences in background methane change. Though this trip did not accomplish its primary goal of detecting any abandoned/orphaned oil & gas wells’ methane leaks (and thankfully, environmentally speaking, that’s a good outcome), we were able to test and prove the minute CH₄ concentration differences that the PMA is capable of discerning.
Be sure to check out more soon-to-come PMA blogs!
תגובות