One of my favorite cars was my late 1980’s SAAB 900 SPG, despite the fact that it almost certainly put my mechanic’s children through college. The worst conversations we had were always about the air conditioning (which I ended up just doing without) because he could not actually be sure how much work would be needed. The potential costs we might discover once he “got in there” amounted to a very deep rabbit hole.
Interconnecting biogas projects to the electric grid always reminds me of those conversations: I never feel like I have discovered all the issues until I am deep into the process. The best one can do is accumulate as many lessons from the past as possible, and hope that over time, there are fewer and fewer mines left unexploded. As federal and state regulators attempt to introduce “fast track” programs for renewable energy, hazards remain. At the outset, I should state that this is not specific advice, but rather general observations and trends that have come to my attention.
For anyone who is not dealing with it directly, interconnection may sound like a foreign language, so let’s break it down a bit. The three most important distinctions affecting the interconnection of an electric generation station to the power grid are: big v. small (typically above and below 20 MW capacity); distribution lines v. transmission lines (small projects can sometimes qualify for distribution connection); and whether jurisdiction over the connection is state or federal (typically transmission lines are federal and distribution lines are state).
For example, a traditional large electric generation station will connect to transmission lines and be under federal jurisdiction, administered by the Federal Energy Regulatory Commission (FERC). This is a complicated process that can cost millions of dollars, requiring a complete FERC review of the facility’s interconnection equipment and the surrounding power grid, and sometimes involving the power plant paying for “upgrades” to the local grid to absorb the power. At the very least the process requires a very expensive study of the local grid, for which the waiting list can be quite long. This case by case review treats each interconnection system as a “custom” system. Remember that word.
Over the past 10 years, FERC has attempted to streamline this process for smaller electric generation stations such as biogas projects, resulting in FERC’s Standard Interconnection Agreements & Procedures for Small Generators, which can be found at FERC’s webpage. FERC is a federal agency, with jurisdiction only over activity that crosses state lines, effectively limiting its purview to transmission-level interconnection. Small projects qualifying for interconnection at the distribution level (the regular power wires on the poles that come to your house) will almost always be governed by state law. However, developers should expect state standards to borrow heavily from the FERC standards.

“Fast Track”

Part of the FERC process is a “fast track” (which definitely deserves to be in quotation marks) for projects under 2 MW, which will presumably be adopted by more and more states. As developers begin to work with these new programs, however, they must be on the lookout for unexpected snags that can slow or halt the process. Fast track programs theoretically speed up the process in two ways: they move the project into a shorter, faster moving wait list (or “queue”), and then process the interconnect application in a shorter and predictable amount of time. It is in the latter task where biogas can encounter delays which do not affect other renewables.
Two (of several, most likely) areas in which streamlining and simplifying efforts available to some other renewables have not yet been put in effect with biogas are substation trips and standardized interconnect system approval. A “trip” is an external disconnect switch, which allows the local substation to shut you down if there is a grid emergency. This can be expensive and complicated, and while the growing consensus is that small solar projects should not need this, I have yet to see a state in which a generator from a biogas project is exempt (although there could be some). A trip is a classic rabbit hole, because the manner in which the communication connection can be physically made between the project site and the substation varies widely, and can cost 10 to 20 times original estimates. The trip problem is not new, but the fact that some other systems such as solar are getting traction for exemption is.
Switchgear and other interconnection equipment for biogas projects are not particularly exotic; there are different configurations and equipment choices, but it’s nothing terribly unusual. Despite that, FERC has no standards for preapproved interconnection systems when it comes to generator engines. In contrast, solar inverters which comply with UL Standard 1741 (Standard for Inverters, Converters, Controllers and Interconnection System Equipment for Use With Distributed Energy Resources) are basically preapproved. However, each biogas genset grid connection is a “custom” system and needs to be reviewed individually. This will affect interconnect approval time, perhaps significantly.
The only one piece of advice I can give anyone who wants to avoid these delays is to inform yourself as completely as possible about the process in advance, and then assume at least five things will go wrong anyway. One very helpful development: FERC and some states have adopted a “pre-application report,” which would provide information about potential project sites in advance. Properly implemented, this type of report could save huge amounts of wasted time and money.
Finally, I would like to stress this is not anyone’s fault. We are changing a huge and complicated electric grid to accommodate a totally new set of generating capacity, and that is not going to go smoothly. The engineers and planners at the commissions, utilities and other grid maintenance organizations who ensure reliable electric service are dedicated professionals who do a very difficult job. Most of us do not appreciate what a monumental achievement a reliable nationwide electric grid is.
Ted Niblock develops biogas projects for NewAg Development.