Willdan Group, Inc. (Willdan) is an American

publicly traded A public company is a company whose ownership is organized via shares of share capital, stock which are intended to be freely traded on a stock exchange or in over-the-counter (finance), over-the-counter markets. A public (publicly traded) co ...

company selling professional technical and consulting services to public and private utilities, public agencies at all levels of government, and commercial and industrial firms. The company operates offices in more than a dozen states, with its key operations in California and New York.

History

In 1964, the company was built by William Stookey and Dan Heil in southern California on a then-unique model of providing outsourced engineering services exclusively to municipalities, especially newly urbanizing cities. Over the next 50 years, the company's expansion has reflected the increasingly complex challenges facing communities, with a forward-looking focus on

energy efficiency Energy efficiency may refer to: * Energy efficiency (physics), the ratio between the useful output and input of an energy conversion process ** Electrical efficiency, useful power output per electrical power consumed ** Mechanical efficiency, a rat ...

energy engineering Energy engineering is a multidisciplinary field of engineering that focuses on optimizing energy systems, developing renewable energy technologies, and improving energy efficiency to meet the world's growing demand for energy in a sustainable man ...

cogeneration Cogeneration or combined heat and power (CHP) is the use of a heat engine or power station to generate electricity and useful heat at the same time. Cogeneration is a more efficient use of fuel or heat, because otherwise- wasted heat from elec ...

Energy Savings Performance Contract Energy Savings Performance Contracts (ESPCs), also known as Energy Performance Contracts, are an alternative financing mechanism authorized by the United States Congress designed to accelerate investment in cost effective energy conservation measur ...

Community Choice Aggregation Community Choice Aggregation (CCA), also known as Community Choice Energy, municipal aggregation, governmental aggregation, electricity aggregation, and community aggregation, is an alternative to the investor-owned utility energy supply system in ...

smart city A smart city is an urban area that uses digital technology to collect data and operate services. Data is collected from citizens, devices, buildings, or cameras. Applications include traffic and transportation systems, power plants, utilities ...

microgrid A microgrid is a local electrical grid with defined electrical boundaries, acting as a single and controllable entity. It is able to operate in grid-connected and off-grid modes.

consulting, and Transactive energy software. In 2006, Willdan Group, Inc. completed its initial public offerings in NASDAQ, becoming a publicly traded company under the symbol WLDN. In 2008, Willdan acquired Intergy Corporation, then renamed Willdan Energy Solutions, offering energy efficiency utility program management. In 2015, Willdan acquired 360 Energy Engineers and Abacus Resource Management, expanding its capabilities into

Energy Service Company An energy service company (ESCO) is a company that provides a broad range of energy solutions including designs and implementation of energy savings projects, retrofitting, energy conservation, energy infrastructure outsourcing, power generat ...

and

services. Willdan acquired NYC-based Genesys Engineering, P.C., in 2016, bringing

Power Engineering Power engineering, also called power systems engineering, is a subfield of electrical engineering that deals with the generation, transmission, distribution, and utilization of electric power, and the electrical apparatus connected to such sy ...

services into its portfolio, with an eye to evolution of U.S. power systems toward

Distributed generation Distributed generation, also distributed energy, on-site generation (OSG), or district/decentralized energy, is electrical generation and storage performed by a variety of small, grid-connected or distribution system-connected devices referred ...

and

microgrids A microgrid is a local electrical grid with defined electrical boundaries, acting as a single and controllable entity. It is able to operate in grid-connected and off-grid modes.

. The

big data Big data primarily refers to data sets that are too large or complex to be dealt with by traditional data processing, data-processing application software, software. Data with many entries (rows) offer greater statistical power, while data with ...

analytics Analytics is the systematic computational analysis of data or statistics. It is used for the discovery, interpretation, and communication of meaningful patterns in data, which also falls under and directly relates to the umbrella term, data sc ...

firm Integral Analytics, Inc. (IA) was acquired by Willdan in July 2017. IA's software solutions help

investor-owned utility Investor-owned utilities (IOUs) are private enterprises acting as public utilities. References Public utilities {{business-stub ...

and

managers solve problems arising from the transformation of an

electrical grid An electrical grid (or electricity network) is an interconnected network for electricity delivery from producers to consumers. Electrical grids consist of power stations, electrical substations to step voltage up or down, electric power tran ...

facing growth in

distributed generation Distributed generation, also distributed energy, on-site generation (OSG), or district/decentralized energy, is electrical generation and storage performed by a variety of small, grid-connected or distribution system-connected devices referred ...

sources, such as

solar power Solar power, also known as solar electricity, is the conversion of energy from sunlight into electricity, either directly using photovoltaics (PV) or indirectly using concentrated solar power. Solar panels use the photovoltaic effect to c ...

and

electric vehicle An electric vehicle (EV) is a motor vehicle whose propulsion is powered fully or mostly by electricity. EVs encompass a wide range of transportation modes, including road vehicle, road and rail vehicles, electric boats and Submersible, submer ...

s, effectively harnessing the power of

renewable energy Renewable energy (also called green energy) is energy made from renewable resource, renewable natural resources that are replenished on a human lifetime, human timescale. The most widely used renewable energy types are solar energy, wind pow ...

and

energy storage Energy storage is the capture of energy produced at one time for use at a later time to reduce imbalances between energy demand and energy production. A device that stores energy is generally called an Accumulator (energy), accumulator or Batte ...

. The

and

sustainability Sustainability is a social goal for people to co-exist on Earth over a long period of time. Definitions of this term are disputed and have varied with literature, context, and time. Sustainability usually has three dimensions (or pillars): env ...

firm of Newcomb Anderson McCormick, Inc. was acquired by Willdan in April 2018, bringing strong relationships as a long-term

, and

green buildings Green building (also known as green construction, sustainable building, or eco-friendly building) refers to both a structure and the application of processes that are environmentally responsible and resource-efficient throughout a building's l ...

consultant for the

University of California The University of California (UC) is a public university, public Land-grant university, land-grant research university, research university system in the U.S. state of California. Headquartered in Oakland, California, Oakland, the system is co ...

California State University The California State University (Cal State or CSU) is a Public university, public university system in California, and the List of largest universities and university networks by enrollment, largest public university system in the United States ...

, and

California Community Colleges System The California Community Colleges is a postsecondary education University system, system in the U.S. state of California.California Education CodSection 70900(added to the Education Code by Chapter 973 of the California Statutes of 1988Assembly ...

, and with

San Francisco Bay Area The San Francisco Bay Area, commonly known as the Bay Area, is a List of regions of California, region of California surrounding and including San Francisco Bay, and anchored by the cities of Oakland, San Francisco, and San Jose, California, S ...

public agencies and utilities. With its November, 2018, acquisition of Lime Energy, Willdan further expanded its presence in the energy market. Lime Energy has delivered energy efficiency programs for 10 of the 25 largest electric utilities and five of the 10 largest municipal utilities in the U.S. Acquisition of The Weidt Group in March 2019 added energy engineering for new construction and a strong presence in the Upper Midwest. In July 2019, Willdan entered a $200 million expanded credit facility to fund future acquisitions, and also announced its acquisition of Onsite Energy Corporation, adding industrial sector clients for Willdan's energy efficiency services. In October 2019 Willdan announced the acquisition of Energy and Environmental Economics, Inc (E3), a data-driven energy analysis and strategy consulting firm headquartered in San Francisco, California. E3 has more than 70 employees across offices in San Francisco, Boston, and New York. E3 generated approximately $16 million in revenue in 2018. Willdan acquired Alternative Power Generation, Inc. (APG), an electrical engineering and construction management firm, in a stock purchase in March, 2025. APG adds significant expertise in

data center A data center is a building, a dedicated space within a building, or a group of buildings used to house computer systems and associated components, such as telecommunications and storage systems. Since IT operations are crucial for busines ...

substation A substation is a part of an electrical Electricity generation, generation, electric power transmission, transmission, and electric power distribution, distribution system. Substations transform voltage from high to low, or the reverse, or pe ...

design and construction management,

microgrid A microgrid is a local electrical grid with defined electrical boundaries, acting as a single and controllable entity. It is able to operate in grid-connected and off-grid modes.

s, EV

charging station A charging station, also known as a charge point, chargepoint, or electric vehicle supply equipment (EVSE), is a power supply electrical device, device that supplies electrical power for recharging plug-in electric vehicles (including batter ...

s, and renewable energy projects for the commercial sector. In 2024, APG generated approximately $37 million in revenue.

References

External links

* * {{Finance links , name = Willdan Group, Inc. , symbol = WLDN , sec_cik = WLDN , yahoo = WLDN , google = WLDN , bloomberg = WLDN:US 1964 establishments in California Companies listed on the Nasdaq Companies based in California Construction and civil engineering companies established in 1964 Energy engineering and contractor companies Construction and civil engineering companies of the United States Software companies of the United States