A rugged LiDAR system for the remote detection of fugitive emissions of methane from shale gas and landfill sites.

我们开发了一种基于激光的仪器，可以扫描低层大气并测量二氧化碳和甲烷等温室气体的浓度。该技术被称为差分吸收激光雷达（DIAL），其精细调谐的扫描激光器可检测半球内多个距离（约5公里）的温室气体大气浓度。该系统的直接应用范围包括测量页岩气行业水力压裂威尔斯井的无组织排放、垃圾填埋场的甲烷排放、国家对《京都议定书》的遵守情况、测量全球碳循环的变化以及观察加州立法刚刚通过的限额和交易计划的影响。DIAL可以扩展到测量其他大气化合物，例如特大城市空气中的气溶胶含量，这是许多政治议程的首要问题。我们的DIAL向大气中发射人眼安全的激光，其波长已知会被感兴趣的气体吸收;激光器还发射不被感兴趣的气体吸收的不同波长的第二光束（参考光束）。后向散射返回信号的差异以及精确的时间分辨率被用于计算通常高达5公里范围内的温室气体浓度分布。我们的系统可以生成感兴趣的温室气体浓度的分布图和地图，并使用我们的建模软件，我们能够精确地确定温室气体的来源。我们的DIAL已经开发了三年，我们正处于需要将其从实验室设备推向现场演示的阶段。我们目前对该系统的经验是，在将其带到野外之前，它需要变得更加坚固-聚焦望远镜连接在望远镜的外部，事实证明，按压望远镜的皮肤会使激光束在太空中移动，从而影响仪器的灵敏度;我们计划重新设计望远镜，使其通过包含外骨骼而更加坚固。激光器本身是为不同的实验室环境而设计的，我们将其用作概念验证。我们的设计将激光器的更敏感部分（光学参量振荡器（调谐激光器）和接收器）安装到单个加工块中，以帮助减少热效应和振动效应。一旦我们加固了该系统，我们将与我们的项目合作伙伴合作，在垃圾填埋场和页岩气（水力压裂）现场进行现场试验。我们的商业机会是提供整个系统-我们将制造望远镜及其激光器/探测器系统，我们将为望远镜的客户提供数据处理选项。

We have developed a laser-based instrument that can scan the lower atmosphere and measure the concentration of greenhouse gases such as carbon dioxide and methane. The technology is known as Differential Absorption LiDAR (DIAL) and its finely-tuned scanning laser detects the atmospheric concentration of greenhouse gases at a number of distances in a hemisphere to about 5 km. Immediate applications of the system range from measuring fugitive emissions from fracking wells in the shale gas industry, landfill emissions of methane, national compliance with the Kyoto Protocol, measuring changes in the global carbon cycle and observing the impact of Cap and Trade schemes of the type just passed in Californian legislation. The DIAL can be extended to measure other atmospheric compounds such as the aerosol loading of the air in megacities, something which is rising towards the top of many political agendas.Our DIAL fires an eye-safe laser into the atmosphere at a wavelength which is known to be absorbed by the gas of interest; the laser also fires a second beam (a reference beam) at a different wavelength that is not absorbed by the gas of interest. The difference in the backscatter return signals together with accurate time resolution is used to calculate the GHG concentration profile at ranges up to typically 5km. Our system produces profiles and maps of the concentration of the GHG of interest and, using our modelling software, we are able to pinpoint just where the GHG came from.Our DIAL has been in development for three years and we are at a point where we need to take it from a laboratory-based device to a field demonstrator. Our experience with the system at the moment is that it needs to be made more rugged before it could be taken to the field - the focussing telescope is attached to the outside of the telescope and it turns out that pressing on the skin of the telescope moves the laser beam in space and thus affects the sensitivity of the instrument; we plan to redesign the telescope so it is more rigid by inclusion of an exoskeleton. The laser itself was built for a different, lab-based environment and we used it as proof-of-concept. We have designs to fit the more sensitive parts of the laser (the Optical Parametric Oscillator (which tunes the laser) and the receiver) into single machined blocks to help reduce thermal and vibration effects. Once we have ruggedised the system, we will undertake field trials at a landfill and shale gas (fracking) site in cooperation with our project partners. Our Business Opportunity is to offer the system as a whole - we would manufacture the telescope and its laser/detector system and we would offer a data processing option to customers of the telescope.