ADA-ES Awarded Contract for Mercury Control System.

Request for Quotations for 30 ACI Systems in First Quarter Affirms Healthy Market

LITTLETON, Colo. -- ADA-ES, Inc. (NASDAQ: ADES) is today providing an update on its sales and supply of activated carbon injection (ACI) systems that control mercury emission from coal-fired electrical generating units. In the first quarter of 2008, ADA-ES was awarded one additional contract for an ACI system to be fabricated and delivered in 2008-2009.

Dr. Michael Durham, President & CEO of ADA-ES stated, "It is our understanding that utilities postponed plans for at least 12 systems due to the uncertainty created by the recent decision by the DC Circuit Court of Appeals against EPA vacating the Clean Air Mercury Rule (CAMR). However, despite the delays caused by the ruling on CAMR, there was significant bid and proposal activity for ACI systems during the quarter, which we believe reflects a growing market to meet the requirements of existing mercury control regulations."

During the first quarter, ADA-ES responded to requests for quotations for 30 ACI systems for plants generating over 10,000 megawatts of electrical power. Many of these will be purchased to meet state mercury control regulations. However, four of the systems are for new power plants. On March 14, 2008, the DC Circuit Court of Appeals ordered the immediate effectiveness of its "mandate" under its prior CAMR decision, ordering that all coal-fired plants currently undergoing the permitting process must include in their permit applications mercury Maximum Achievable Control Technology (MACT), which requires 90% mercury removal from emissions. ACI Systems are considered MACT for new plants. In addition to U.S. state regulations and new power plant requirements, seven of the ACI systems bid by ADA-ES were for Canadian utilities, which the Company believes reflects an additional emerging market.

In conclusion, Dr. Durham commented, "We are encouraged by the continued growth of the mercury control market, which is certainly vital to our near-term and long-term revenues. The sale of ACI equipment was our largest revenue source in 2007, and we expect the same will be true in 2008. However, in 2009 and 2010, the 82 total systems sold by suppliers to date, as well as new systems being ordered, will all require activated carbon on a continuous basis. We are preparing to serve this market through our interim AC supply plans and new AC production facility that is in progress."

About ADA-ES

Headquartered in Littleton, CO, ADA-ES is a leader in clean coal technology and the associated specialty chemicals. The Company develops and implements proprietary environmental technology and specialty chemicals that enable coal-fueled power plants to enhance existing air pollution control equipment, maximize capacity and improve operating efficiencies. Through its largest and fastest-growing segment, Mercury Emission Control, ADA-ES supplies activated carbon injection systems, mercury measurement instrumentation, and related services. Additionally, the Company is implementing plans to produce and supply activated carbon.

This press release contains forward-looking information within the meaning of Section 21E of the Securities Exchange Act of 1934, which provides a "safe harbor" for such statements in certain circumstances. These statements are based on current expectations, estimates, forecasts, projections, beliefs and assumptions of our management. Such statements are prefaced by words such as "anticipates," "believes," "hopes," "expects," "intends" and "plans," the negative of such words, or words of similar meaning. The forward-looking statements contained in this release include: our expectations concerning the growth of the market for mercury control and the size of that market; the reasons for postponement of ACI systems contracts, our expectations regarding winning additional competitive bids for ACI systems and our expectations concerning implementing our plans for expanding our mercury control business into AC supply. Such statements involve significant risks and uncertainties, which could cause actual events or results to differ materially from those discussed in the forward-looking statements as a result of various factors, including, but not limited to, changing economic conditions and market demand for ADA-ES' products and services, changes in technology, our ability to win competitive bids for ACI systems, the availability on reasonable terms of either private and/or public funding necessary to meet our expansion plans for the AC business, and changes in laws or regulations, among other factors, all of which we discuss in greater detail in our filings with the U.S. Securities and Exchange Commission, with particular emphasis on the risk factor disclosures contained in those filings. You are cautioned not to place undue reliance on the forward-looking statements made in this release, and to consult filings we make with the SEC for additional discussion concerning risks and uncertainties that may apply to our business and the ownership of our securities. The forward-looking statements contained in this press release are presented as of the date hereof, and we disclaim any duty to update such statements unless required by law to do so.