Under ARPA-E’s statutory charter, one of our key goals is to develop technology that contributes to the reduction of energy-related emissions. Our recently announced FLExible Carbon Capture and Storage (FLECCS) program - led by Program Director Dr. Scott Litzelman - focuses on this goal, by developing CCS technologies that enable power generators to be flexible and responsive to grid conditions in a high variable renewable energy (VRE) penetration environment. As the nation’s grid continues to evolve towards lower-carbon systems, FLECCS identifies that a need for flexible commercially scalable and deployable carbon capture and sequestration technologies has emerged to ensure all energy sources can contribute to low-cost, low-carbon electricity systems.

Prior to launching the FLECCS program, Dr. Litzelman explored this white space at the 2019 ARPA-E Energy Innovation Summit with his fast pitch, “FLECCS Yourself Before You Wreck Yourself”. We recently sat down with Dr. Litzelman to get some additional insight into the FLECCS program, and the needs it aims to address.

What drove you to create the FLECCS program?

I was trying to understand the disconnect between CCS—a technology that many (but not all) energy experts think is needed for decarbonization but is struggling in terms of deployment—and renewables, which are being deployed broadly. I think the value of CCS becomes apparent once a grid has already been partly decarbonized, but such a grid would already have a large share of power from renewables. Therein lies the catch: the grid that CCS-equipped power plants will be exposed to will be quite different than the grid they were originally designed for.

What challenges does VRE create for the grid? How can flexible CCS technologies help to mitigate those challenges?

Electricity grids were designed for centralized power plants, transmission and distribution lines, and end use at residential, commercial, and industrial sites. Developments like VREs, energy storage, demand-side management, etc., are changing that paradigm. The output of renewables isn’t just variable: it’s uncertain, which creates huge challenges for system planners and grid operators. For example, we know when the sun will rise and set. But it’s harder to predict exact times and locations of cloud cover. Several studies have shown that the cost of deep decarbonization can be much lower if diverse and complementary technologies are employed. Flexible CCS could be part of that mix.

In the FLECCS FOA, there is an emphasis on economic concepts like the Locational Marginal Price (LMP) of electricity and Net Present Value (NPV) of projects. Why?

I wanted FLECCS to be technology agnostic. We are not specifying which technologies will be best; we’re not even specifying specific metrics like CO2 capture rate and power plant ramp rate. Rather, all project teams will use an economic framework that my colleague, Max Tuttman (ARPA-E Technology-to-Market advisor), and I developed. We will provide sample electricity price signals that represent a grid with a high VRE penetration and several carbon abatement scenarios. Teams will use those economic inputs to design CCS processes with the goal of optimizing the NPV of CCS-equipped power plants. NPV is a way of measuring the value of a given investment and helps developers to decide whether or not to move forward with a project. We are also going to use capacity expansion models, which identify optimal portfolios of grid resources given certain cost and performance characteristics, to understand whether the processes developed in FLECCS will be valuable in a future grid.

Why aren’t existing CCS systems as flexible as power plants like natural gas combined cycle units?

We actually don’t know how flexible CCS systems really are because the commercial systems today—in Texas and Saskatchewan—are running under baseload operating conditions. There have been some smaller, pilot-scale CCS systems that have been operated dynamically, and the early data suggest they do have some flexibility. But the economic signals that we will provide in FLECCS will demand more flexibility that anything that has been shown to date. One area of uncertainty, for example, is how far a CCS process could turn down. That means processing much less CO2 than it was designed for. Certain parts of the process might be unaffected, but there are other parts that might underperform or even fail under flexible operating conditions.

The FOA says that optimal technology solutions could differ substantially from a CCS processes tailored for 90% CO2 capture from a power operating under baseload conditions. What might some of these differences be?

To design a CCS process, one must understand how the power plant will be operated. The grid will not require a power plant to be running at full output all the time, which changes the tradeoffs between CCS capital costs and efficiency. For a plant running all the time, it may be worth it to spend more capital for a more efficient process. But for a plant with a lower capacity factor, it may be economically superior to build a process with lower capital costs even if it’s less efficient. Another concept is to include some form of storage so that the power plant and CCS unit are running under steady conditions, but output power to the grid only when prices are high enough to make a profit. Again, we’re not telling project teams what their process should look like. We are giving them conditions that reflect a future grid and asking them to design and build CCS processes that provide the most value.

For more information on ARPA-E’s FLECCS program click HERE, and to apply for funding, click HERE.