Grid Interactive Efficient Buildings - Grid to Building Interface
Last week we took a look at control hierarchy and the different layers if control at play depending on the building to grid use case. This week lets take a closer look at building to grid interfaces with a focus on the local grid to GEB, we will cover wholesale to GEB and local grid coordination in an upcoming blog.
Today for more traditional demand response programs the utility operators have very limited (if any) direct monitoring and control to building and DER. Where aggregators and end device manufactures such as smart thermostats take a
highlevel, system wide and often day ahead or pre-scheduled request from the utility to back down load. Otherwise time of use pricing via advanced metering provdes some level of load shaping capability but is typically set and forget and generally does not change with real time or local grid needs. This lack of direct monitorig control capability for grid operators makes reliance on #GEBs to support grid needs chalenging. However in contrast, it’s very challenging if not impossible for grid operators to monitor and control thousands or millions of individual GEBs, plus building owners are concerned having grid operators directly control their buildings. So how to overcome this major hurdle?
Utilities are currently deploying #ADMS and #DERMS software to help grid operators manage the distribution via increased grid sensing, SCADA, real time power flow modeling and greater awareness and modeing of DERs. Although the exact definition and capabilities of DERMS is still being defined in the industry, the general capability is to help grid operators have better viability to DERs and therefore increasing the ability to rely on DERs to support the grid such as NWAs. These utility softwares are a critical step in grid operators ability to leverage GEBs to support grid needs. However whats the communication link between these utility softwares and the #GEBs?
Seeing as we are focusing on local utility to GEB in this blog we will focus on local utility use cases such as local load relief, generation curtailment avoidance, NWAs etc. For use cases it likely optimal to have communication take place from the DERMS software to the GEB whole building level BMS either directly for larger C&I GEBs or via a 3rd party aggregator for smaller GEBs. Where the former likely via utility grade direct communications and the latter via a Cloud-internet based integration from DERMS to the 3rd party software and likely Cloud-internet connection from 3rd parties to smaller C&I BMS and HEMS (Home area management systems). Devices such as smart inverters for generation and storage and smart meters will need to be integrated into BMS and HEMS for holistic GEB operations. Regarding Cloud based utility to GEB connectivity cyber security plays and important consideration especially when utilities have greater reliance on a significan’t amount of smaller GEBs that if compromised could have disastrous impacts on the grid. Lastly as mentioned in the last blog there is a BMS gap in industry today for small and medium C&I buildings that aggregators would need connectivity to in order to implement #GEB building to grid capabilities and as such is were platforms such as #VOLTTRON can play a key role here.
On the planning side on building to grid interface, utility planners need to consider and be aware of GEB opportunities to solve local grid needs. To help address this, utility databases and GIS models are evolving to capture locations where GEBs reside along with associated DER capabilities, stemming from interconnection studies.
Also building owners need to be aware of hosting capacity limitations for increased load from all electric buildings, energy storage during charging and EV chargers and hosting capacity limitations for generation such as solar PV. Fortunately many utilities have or are developing publicly available generarion and load hosting capacity maps.