Should airports have their own microgrids?

8 October 2018 (Last Updated October 10th, 2018 09:43)

After Atlanta Hartsfield-Jackson International Airport, the busiest airport in the world, experienced a major power supply disruption on 17 December 2017, the Rocky Mountain Institute (RMI) was awarded a $450,000 research grant to develop a microgrid implementation toolkit to help airports avoid disaster. So what will the toolkit need to cover and how exactly do microgrids work in this setting?

Should airports have their own microgrids?
Are microgrids the future of airport power?

A fire-related, eleven-hour power outage at Hartsfield-Jackson Atlanta International Airport in December last year caused more than 1,000 flights to be delayed, and meant economic and emotional turmoil for passengers and flight operators alike. In January 2018, Delta Air Lines announced that the lone incident had cost the company between $25m-$50m in pre-tax income.

The conversation since has focused on whether the installation of a microgrid could have avoided this economic disaster. A microgrid is a local energy system that can work both as part of the grid, but it can also disconnect to operate independently, powered by battery storage, conventional generators or renewable power sources.

Global energy non-profit the Rocky Mountain Institute (RMI) has recently been awarded a $450,000 grant from the National Academies of Sciences, Engineering and Medicine’s Transportation Research Board to develop an airport microgrid ‘toolkit’ aimed at helping airports understand the economic and operational impact of installing a microgrid. RMI’s director of sustainable aviation at Adam Klauber explains further.

Elliot Gardner: Why are microgrids being called the future of airport power?

Adam Klauber: Microgrids are increasingly the hot topic in North America and beyond, and airports in the US are experiencing an increasing frequency of power outages. Because of that, airports are essentially ground zero for having their business operations disrupted. So they’re looking for solutions.

A common method in the past has been backup power from extra diesel generators, but increasingly as renewable energy and battery storage come down in price, airports would prefer other alternatives.

With a microgrid, they have the ability to manage their utility bills more effectively due to technology that can effectively reduce their demand on the grid during times of peak usage when rates are higher. Airports can also help support the grid when there’s a ‘demand response event’. Facilities can run their own back-up power and reduce their draw on the grid, and in response to participating in an organised system, they actually get payment back for demand response.

EG: Why are airport power outages on the rise?

AK: Some of it has to do with the age of the grid and infrastructure investment that has been delayed. We’re at a point where we need to replace key parts of the grid – transformers, substations, etc. Growing demand in certain areas puts acute strain on the system. We’re also seeing more acute weather incidents, so more extreme weather – wind especially, and also flooding.

Winds are on average getting more powerful – they have a higher chance of knocking out power lines. Most airports are not on high voltage lines, which are the most resistant to wind damage. We are seeing higher frequency lightning events in the US too and that’s a concern. Those are the two major factors.

EG: Why is the RMI microgrid implementation toolkit needed?

AK: Airports have priorities such as making sure they have continuity of operations and that everything is conducted safely. So microgrids are a new area for them when they’re already burdened with their existing responsibilities.

Airports don’t necessarily have the expertise and know-how to start the discussion around microgrids alone. Microgrids require considerable collaboration with stakeholders, including the tenants of the airports (such as the airlines and concessionaires), local regional public utilities, the FAA and emergency response participants.

So airports are looking for expertise and the National Academy provided this grant to provide information for airports so they know where to start and give them a general sense of the cost, and ambition level in regards to the size of facilities, economics and so on.

EG: The conversation surrounding microgrids picked up after a power outage at Atlanta Airport. What advantage would microgrids have in that situation?

AK: The approximate cause of the power outage was a transformer that went down. There wasn’t an alternative redundancy for that transformer and it was at a critical point on the line. A microgrid would have been designed to have that redundancy, to make sure that critical point was backed up.

A microgrid would also provide instantaneous power. They would never have a slow-down or period where they’re starting back-up engine generators; they would have coverage in the form of battery storage or fuel cell power, which would kick in immediately, so they would be able to continue operations without any pause. That’s the reason why Atlanta is looking at a microgrid and not just putting in additional electric generators.

Another benefit is that there would not have to be periodic inspections of engine generators, and diesel fuel wouldn’t be stored on-site. The microgrid would allow airports to play to the energy market so to speak. They could use their energy storage when prices are high during the day and would have an asset that would be part of their natural operations, and not something that they would have to periodically deploy. So presumably, it would be up to speed and ready whenever they needed it, whether for critical usage, or for when the economics are beneficial.

EG: How would the cost of installing a microgrid weigh up versus potential economic gains?

AK: To be perfectly candid, microgrids will not make economic sense in all locations in the US. For markets where energy prices are low, the economic case for a microgrid won’t be as strong. Perhaps an airport would decide that it would just implement a very small microgrid that supports emergency functions, the lowest electrical load possible. That may be a good choice for emergency preparations.

In other markets such as California, where you have a very high price of electricity, the economics will be much better and there will clearly be an economic incentive, in addition to emergency preparedness. It will depend very much on the location. Our toolkit will help an airport understand the economics and factor that in as one of their key considerations.

One of the reasons why there’s a use case here, and why microgrids are such a focus for airports compared to other industries, is that when you have a cancelled flight, it’s a direct economic cost that cannot be made up. That’s revenue that airlines lose and there are very few other parts of our economy that are that sensitive to disruption. Because of that dynamic, we believe airports will be excellent candidates for microgrids, because the impacts of power outages are particularly acute.