EnerNOC was among the largest providers of energy intelligence software and services for commercial, institutional, and industrial customers, as well as electric power grid operators and utilities. It chiefly provided energy intelligence software and services.

EnerNOC was first established by Timothy G. Healy and David Brewster, as EnerNOC, LLC in New Hampshire from December 2001 until June 2003. On June 5, 2003 EnerNOC was incorporated in Delaware. Until the sale of the company in August 2017, their corporate headquarters was at One Marina Park Drive, Suite 400, Boston, Massachusetts 02210.

EnerNOC went public in 2007 on the NASDAQ stock exchange at US$26 per share followed by a rally to US$50 per share in spite of reporting two consecutive annual losses. EnerNOC provided the strongest IPO by percentage increase in the green energy sector for the year. The offering included 3.75 million shares. US$98 million was raised with underwriters Credit Suisse and Morgan Stanley.

EnerNOC owned numerous subsidiaries around the world. In 2009, EnerNOC bought Cogent Energy and acquired eQuilibrium Solutions, which provides carbon accounting solutions. In March, 2010, EnerNOC bought SmallFoot, LLC, a company that makes wireless systems to manage demand for smaller facilities. Tim Healy, CEO of EnerNOC, said of the acquisition, "Going deeper into this underserved market represents a large growth opportunity for our company. SmallFoot gives us additional technology to unlock all forms of demand response and deploy our full suite of applications in this exciting market."

In late 2010 and early 2011, respectively, EnerNOC announced agreements to acquire Global Energy Partners and M2M Communications. Global Energy Partners is "an industry leader in designing and implementing utility energy efficiency and demand response programs." M2M Communications specializes in wireless technology solutions for energy management and demand response.

Since early 2014, EnerNOC acquired five additional companies: Activation Energy, an Irish provider of demand response; Entelios, a German demand response provider; EnTech, a global utility bill management software provider; Pulse Energy, a Vancouver-based provider of utility customer engagement software; and World Energy, an energy procurement software company.

As of March 31, 2015, EnerNOC had over 70,000 sites using its services and software, including commercial buildings, supermarkets, industrial sites, and universities. EIS for enterprise includes budgeting and procurement, utility bill management, facility optimization, visibility and reporting, project tracking, demand management, and demand response. EnerNOC's EIS solutions for utilities help maximize customer engagement and the value of demand-side resources, including demand response and energy efficiency.

EnerNOC is the world's leading provider of demand response. If a utility company or grid operator has a sudden increase in demand, EnerNOC communicates with customers connected to its network in order to reduce energy use. This can restore balance to the system and prevent the need for the utility to purchase more expensive electricity or even avoid blackouts or brownouts in some cases. During a demand response dispatch, a participating site might switch over to a generator, reduce air conditioning or lighting usage, or power down appliances or other equipment that are not being used. If a site reduces its energy usage during these dispatches, the utility company or grid operator will pay EnerNOC and the customer for this service. Customers are also paid for being on call to reduce demand, thereby providing a superficial, but accountable, capacity to the grid operator or utility. EnerNOC offers a web-based demand response software application that enables its customers to track their own individual energy reductions.

Was the Co-Founder, Chief Executive Officer and Executive Chairman since its founding of Enernoc, Inc. He has previously worked for Northern Power Systems, Inc., Merrill Lynch as a Financial Analyst, International Fuel Cells (now UTC Fuel Cells), Commonwealth Capital Ventures, Contemporary Investment Management as a Senior Associate, and worked as Analyst of Commonwealth Capital Ventures, Commonwealth Capital Ventures III, L.P. and Commonwealth Capital Ventures IV, L.P. He also co-founded and served as an Associate for the public company Student Advantage. He holds a Bachelor of Arts in Government and Economics from Dartmouth College and a Master of Business Administration from the Amos Tuck School of Business Administration at Dartmouth.

David Brewster was the President of EnerNOC and one of its founders.

ENOC Securities Corporation, was founded as a Massachusetts securities corporation. Its purpose is to conduct short-term investment of temporary surpluses.

EnerNOC received a $10 million contract in 2010 to track how much energy state-owned facilities use in Massachusetts. The contract is funded with stimulus money through the United States Department of Energy. Massachusetts hopes to use the study to shave 5 to 15 percent of its annual energy expenses, as well as help shift to alternative energy sources. EnerNOC will be receiving metering information from 470 state-owned buildings, including schools, prisons, and municipal buildings. The information received will include how much energy is being used and where the energy is coming from (for example natural gas, oil, or renewable energy sources). In the summer of 2010, EnerNOC contracted with the Tennessee Valley Authority, the nation's largest public power company, for a 10-year, 560 megawatt demand response contract that represented an addition of 400 MW to TVA’s existing deployment of approximately 160 MW with EnerNOC.

EnerNOC, which stands for Energy Network Operations Center, has won numerous awards for its technology, customer service, and industry. Some of these awards include two 2009 Smart Grid Product of the Year Awards from the Technology Marketing Corporation and Intelligent Communications Partners. EnerNOC’s Boston Business Journal also honored EnerNOC’s EfficiencySMART Insight with a 2011 Best Green Practices Award in the Invention category.

EnerNOC was also named one of the Boston Globe's Top 100 Places to Work in 2009 and 2010, as well as one of the Boston Business Journal's Best Places to Work in 2008.