Renewable sources of energy continue to grow as a percentage of energy provided to electrical power grids. In a CERAWeek 2019 panel, Renewables & Gas Integration: Is there an efficient frontier?, Emerson’s Bob Yeager shared his perspectives on the role of technology and automation in managing this energy mix.
Panel moderator, IHS Markit’s Tim Gardner open by showing some statistics on how the incremental costs of adding renewable sources of energy grows rapidly as more carbon-based sources of power generation are reduced. One panelist noted that this frontier between natural gas generation sources and renewable sources is very market specific and not common across all regions.
One way to address the increasing renewable energy percentage is to invest in energy storage technologies including batteries, thermal storage, and other forms based on what’s available in the range. Decarbonization is also occurring by replacing coal with natural gas fuel for electrical generation.
Bob showed a slide with a load profile of an electrical power generation facility in Colorado. Wind energy creates such variability it creates thermal stress on the generators in the plant. Natural gas more and more is the moderating force that must handle the swings.
Bob noted that Asia is growing coal usage as a source of electrical generation, but on a per capita basis, the US is still the largest consumer of electrical power.
Plants more than ever must react quickly to changes in frequency on the grid. Automation can help by spinning up generation capacity more quickly and maintaining spinning inertia for when the demand is required and the renewable source drops off.
From a reliability standpoint, additional sensing capabilities combined with analytics can provide predictive maintenance to avoid unplanned shutdowns. Given the swings in the supply side, removing unplanned downtime becomes even more important in guaranteeing supply for customers.
In question about tradeoffs between renewable and natural gas sources of power generation, policy makers must consider the increasing incremental costs that will be passed on to their constituencies.
Bob was asked about the limits of natural gas sourced plants. He noted that gas plants can respond quickly to load changes, more quickly that coal plants. The issue is the markets are not designed for big swings. Power plants must provide the power required to maintain grid stability, but contractually may not be getting paid to provide this power beyond existing commitments. In world of more stable supply of power generation, these contractual arrangements worked very well, but many must be reworked given the variable supply.
Bob closed is remarks with a question about how advancing battery technology can help with grid stability. He noted that while battery solutions are great for local wind and solar farms, they cannot provide the level of grid stability required that the inertia of large spinning turbines to provide instantaneous supply to demand changes. He explained it is basic physics.