A New Equation for a Smart Energy Campus

Published: Mon 13 Apr 2015
A blog entry by Christine Hertzog

Contributed by:

Christine Hertzog
Managing Director
Smart Grid Library

Christine Hertzog's Blog

We're featuring guest authors over the next few weeks.  This article by Robert D. Cormia, a member of the Foothill College Engineering Faculty, talks about a new equation for energy intelligence - where ei = cm3 (for continuous monitoring, modeling, and management).  Foothill College is located in Los Altos Hills, California, in the heart of Silicon Valley.

Foothill College has been engaged in a strategy that integrates building energy monitoring and management with enhanced distributed generation capabilities.  It’s an important first step on a path that could lead to becoming a 'managed energy grid'. Towards this end, Foothill College has developed a multi-tiered model that will integrate building energy sensors with building automation controls, measuring heat exchange of hydronics (heating and cooling from a central plant); a campus-wide energy management system; inverter output from 1.5 MW solar PV and 240 KW cogeneration (heat and power); an Energy Information System (EIS) that will monitor, model, and display the energy flows into buildings and from our onsite generation and utility feed; and finally the capability to synchronize energy generation and use, and or load shift (demand shift) in a utility business model called Integrated Demand Side Management (IDSM).

The logic and premise for this future energy system is based on a three-tiered stack. First, a smart energy campus begins with understanding when, where, and how energy is being used. This leads to a better understanding of basic building operation, i.e. are building systems operating correctly, and can we control buildings precisely enough to manage energy with occupancy and use?

The second tier of the smart energy stack is significant onsite energy production from 1.5 MW solar PV and 240 kW of cogeneration heat and power, which provides 45% of Foothill's annual electrical demand and 50% - 100% of our peak power demand. At times this generation exceeds campus load, and Foothill exports electrical energy, which currently isn't stored to offset energy at other demand peaks.

The third tier of the stack is the analytics and visualization platform for understanding power flows throughout the day, and displaying energy use at a building and campus level. This Energy Information System (EIS), transcends the energy management and building automation software (EMS/BAS); with such a system, we would begin to model an enhanced generation capability of additional solar PV and battery storage, mainly used to generate and store electrical energy during the day, and release it in the early evening, where we often experience our greatest power demand. In order to leverage additional onsite generation, without swamping the outer distribution grid (called “backfeed”), the generation and release of energy must be carefully managed.

The EIS informs the campus energy manager about how energy generation assets, e.g. solar PV, cogen, and storage, can be combined with Automated Demand Response (ADR) to help the utility power grid better respond to large power demands, and/or shift the campus peak energy demand away from the utility¹s peak demand, which can also cause high time of use (ToU) charges. IDSM, or Integrated Demand Side Management, fits well with large distributed generation behind the meter, especially college campus distributed energy systems. In the utility model of the future, managed energy grids will participate in grid optimization, using a multilayered energy monitoring and management platform, and leveraging our new equation to deliver comprehensive and actionable Energy Intelligence.