A Better Way to Measure Climate Footprints

Chapter 3 presents the Oil Climate Index plus Gas (OCI+), the first open-source tool that assesses and compares the different climate effects of the wide range of oils produced around the world, taking into account upstream, midstream, and downstream emissions. The chapter walks through the motivation behind creating the OCI+ with collaborators from Stanford University and the University of Calgary. The underlying models composing the OCI+ are discussed and visualized in detail. Model data and uncertainty are fleshed out. The chapter discusses methods for evaluating OCI+ emissions using remote sensing, satellites that spot flares from space, and an expanding array of methane measurement instruments. Possible avenues to build out the OCI+ to include other air pollutants are presented. The chapter concludes by laying out estimated ranges of currently modeled emissions intensities of global oil and gas supplies.

A Constellation of Satellites Hunting Methane Leaks Is Launching Soon

A blowout in Ohio in 2018 was the first ever where the emissions could be measured from space, though it was at best a rough estimate based on data gathered on the 13th day after the XTO Energy well control event began. A year later, a blowout of a Devon well near Victoria, Texas, was measured starting the day after it occurred, with data collected on 3 days over the next 2 weeks. Using the measurement of carbon dioxide, it was estimated that the flare was 87% effective in burning about 4,800 metric tons of the leaking methane gas. Emission estimates varied wildly, and both the Ohio (Pandey et al. 2019) and Texas (Cusworth, Duren, Thorpe et al. 2020) efforts to use satellites led to technical papers to consider how they addressed this challenge. For those with blowouts next year, chances are a lot better methane-emission data would be available because of the launch of a constellation of specialized methane-measurement satellites by the two groups that played a key role in the earlier tests. In presentations at CERAWeek by IHS Markit, GHGSat said it has two methane-detection satellites in orbit and plans the launch of eight more, and the Environmental Defense Fund (EDF) said it is moving forward with the launch of its first one next year. Both are aiming to cover the lion’s share of oil and gas operations and measure the flow rate of the gas rather than concentrations in the atmosphere. They said they can do that far more accurately than was possible with the general-purpose climate observation satellites by focusing their equipment on the wavelength of methane. GHGSat said its satellites, which are about the size of a microwave oven, can measure the potent greenhouse gas from an elevation of 500 km and up. They are placed in polar orbit, which allows them to cover the globe every 2 weeks as the Earth rotates. Launching more satellites will allow more frequent looks. There are differences in the GHGSat and EDF designs, reflecting their contrasting missions. The Canadian company GHGSat, whose satellite initiative was initially supported by Schlumberger and the Oil and Gas Climate Initiative, is building tiny satellites with extremely high resolution to serve clients in the oil and mining businesses. During the presentation, Stéphane Germain, chief executive officer of GHGSat, displayed an image and said its satellites can tell if the methane is “coming from a particular facility and even tell what part of the facility it is coming from.” The company also sells the services of similarly equipped planes that can create more-detailed images using similar equipment at elevations of 3000 m and higher. EDF raised $100 million from donors, including Elon Musk, and has hired Raytheon to build a satellite equipped with a detector from Ball Aerospace. It can survey an area that is 260 km wide. That is far wider than the GHGSat satellites, which have the advantage of being able to zero in on smaller details when looking for leaks. The environmental group points out its device is more sensitive to methane emissions, detecting levels down to two parts per billion.

Construction and Operation of a Respiration Chamber of the Head-Box Type for Methane Measurement from Cattle

This paper aims to describe the construction and operation of a respiration chamber of the head-box type for methane (CH4) measurements in bovines. The system consists of (1) a head box with a stainless steel frame and acrylic walls, floor, and ceiling; (2) a stainless steel feeder; (3) an automatic drinking water bowl; (4) a hood made from reinforced canvas; (5) an infrared (IR) CH4 gas analyzer, a mass flow generator, a data-acquisition system; and (6) a steel metabolic box. Six assays were conducted to determine the pure CH4 recovery rate of the whole system in order to validate it and comply with standards of chamber operation. The gravimetrical method was used for the recovery test and the recovery rate obtained was 1.04 ± 0.05. Once the system was calibrated, measurements of CH4 were conducted using eight animals consisting of four Holstein cows with a live weight of 593.8 ± 51 kg and an average milk yield of 23.3 ± 1.8 kg d−1 and four heifers with a live weight of 339 ± 28 kg. The CH4 production values were 687 ± 123 and 248 ± 40 L CH4 d−1 for cows and heifers, respectively. The CH4 yield was 19.7 ± 3.4 g and 17.1 ± 3.4 g CH4 kg−1 of dry matter consumed for cows and heifers, respectively. These results are consistent with those reported in the literature.

Comparison Between Non-Invasive Methane Measurement Techniques in Cattle

The aim of this trial was to study the agreement between the non-dispersive infrared methane analyzer (NDIR) method and the hand held laser methane detector (LMD). Methane (CH4) was measured simultaneously with the two devices totaling 164 paired measurements. The repeatability of the CH4 concentration was greater with the NDIR (0.42) than for the LMD (0.23). However, for the number of peaks, repeatability of the LMD was greater (0.20 vs. 0.14, respectively). Correlation was moderately high and positive for CH4 concentration (0.73 and 0.74, respectively) and number of peaks (0.72 and 0.72, respectively), and the repeated measures correlation and the individual-level correlation were high (0.98 and 0.94, respectively). A moderate concordance correlation coefficient was observed for the CH4 concentration (0.62) and for the number of peaks (0.66). A moderate-high coefficient of individual agreement for the CH4 concentration (0.83) and the number of peaks (0.77) were observed. However, CH4 concentrations population means and all variance components differed between instruments. In conclusion, methane concentration measurements obtained by means of NDIR and LMD cannot be used interchangeably. The joint use of both methods could be considered for genetic selection purposes or for mitigation strategies only if sources of disagreement, which result in different between-subject and within-subject variabilities, are identified and corrected for.

Effect of measurement duration in respiration chambers on methane traits of beef cattle

Records on 1043 young Angus heifer and bull progeny from 73 sires, measured for methane production in respiration chambers, were used to evaluate the accuracy of a 1-day measurement relative to 2-day measurement duration. The traits assessed were dry matter intake (DMI, kg/day), methane-production rate (MPR, g/day), methane yield (MY, MPR per unit DMI) and four residual methane (RMP, g/day) traits. The RMP traits were computed as actual MPR minus expected MPR, where the expected MPR were calculated from three widely used equations. The expected MPR for the fourth RMP trait was computed by regressing MPR on DMI, using the data from the study. Variance components, heritability, phenotypic and genetic correlations, and the efficiency of selection using 1-day compared with 2-day measurement were used as assessment criteria. The environmental variance for the 2-day measurement was slightly lower than that of the 1-day measurement for all the traits studied, indicating that the addition of an extra day of data was effective in reducing the amount of unexplained variation in each trait. However, these minor reductions did not have a major impact on accuracy; hence, very high phenotypic (rp of 0.91–0.99) and genetic (rg of 0.99 for each trait) correlations were obtained between the two measurement durations. The very high genetic correlation between the two durations of measurement indicated that, at the genetic level, the 1-day duration is measuring the same trait as the 2-day measurement duration. Any enteric-methane emission-abatement strategy that seeks to reduce MPR per se, may have a detrimental impact on ruminant productivity through a correlated reduction in feed intake; hence, MY and the RMP traits are likely to be the traits of interest for genetic improvement. Efficiency of selection for MY and the RMP traits ranged from 0.96 to 0.99, which implies that there would be less than 5% loss in efficiency by adopting a 1-day relative to a 2-day methane-measurement duration. While the throughput of the respiration-chamber facility can be increased by adopting a 1-day measurement duration, additional resources, such as holding pens, would be required to take advantage of the extra day.

Global beef cattle methane emissions: yield prediction by cluster and meta-analyses

Methane yield values (MY; g methane/kg dry-matter intake) in beef cattle reported in the global literature (expanded MitiGate database of methane-mitigation studies) were analysed by cluster and meta-analyses. The Ward and k means cluster analyses included accounting for the categorical effects of methane measurement method, cattle breed type, country or region of study, age and sex of cattle, and proportion of grain in the diet and the standardised continuous variables of number of animals, liveweight and MY. After removal of data from outlier studies, meta-analyses were conducted on subsets of data to produce prediction equations for MY. Removing outliers with absolute studentised residual values of >1, followed by meta-analysis of data accounting for categorical effects, is recommended as a method for predicting MY. The large differences among some countries in MY values were significant but difficult to interpret. On the basis of the datasets available, a single, global MY or percentage of gross energy in feed converted to methane (Ym) value is not appropriate for use in Intergovernmental Panel on Climate Change (IPCC) greenhouse accounting methods around the world. Therefore, ideally country-specific MY values should be used in each country’s accounts (i.e. an IPCC Tier 2 or 3 approach) from data generated within that country.

PEMBUATAN BIOGAS DENGAN VARIASI STARTER RAGI DAN KOTORAN SAPI BERBAHAN BAKU SAMPAH ORGANIK

This study aims to determine the composition of the right starter mixture to produce optimal biogas, knowing the temperature (in digester) at the time of fermentation, knowing the effect fungal growth on the levels of biogas. Processing organic waste in small pieces given water and starter, put in bottle and covered with balloon, last process fermentation 45 days. Then samples tested using Methane Measurement System, Carbondioxide, Humidity and Temperature. Then obtained mixture 10% starter cow dung and 90% organic waste CH4 35.79 ppm and CO2 1763.34 ppm, 20% cow dung and 80% organic waste CH4 12.12 ppm and CO2 740.55 ppm, 30% cow dung and 70% organic waste, CH4 14.08 ppm and CO2 858.87 ppm, yeast 10% and organic waste 90% CH4 9.78 ppm and CO2 860.98 ppm, 20% yeast and 80% organic waste CH4 166.08 ppm and CO2 1185.35 ppm and yeast mixture 30% and 70% CH4 organic waste 16.66 ppm and CO2 927.39 ppm. The yeast mixture 20% and 80% organic waste produces most optimal CH4 with temperature in digester at fermentation 30.11 °C with value 206.76 ppm while mixture 10% cow dung and 90% organic waste produces highest CO2 at temperature 30.4 °C with value 2527.57 ppm.