
                     ENERGY CONVERSION DEVICES ANNOUNCES
                 THIRD QUARTER FISCAL 2004 OPERATING RESULTS
                 -------------------------------------------

      ROCHESTER HILLS, Mich., May 17, 2004 - Energy Conversion  Devices,  Inc.
(ECD Ovonics)  (NASDAQ:ENER)  announced  today its  operating  results for the
third  quarter ended March 31, 2004.  Revenues were $16.5 million  compared to
$13.6  million in the third  quarter  last year.  The  Company's  net loss was
$12.3 million for the third quarter  compared to a loss of $9.1 million in the
same quarter last year. On a per-share  basis,  the loss was $.49 in the third
quarter of Fiscal  2004  compared to a loss of $.41 in the same  quarter  last
year.

      The financial results for the three months and nine months ended March
31, 2004 and March 31, 2003 are shown in the following table:

                                        Three Months Ended     Nine Months Ended
                                             March 31,             March 31,
                                        -------------------  ------------------
                                          2004      2003       2004      2003
                                        --------  --------   --------  --------
                                        (in thousands, except per-share amounts)
Revenues
  Product Sales                         $  8,585  $  4,857   $ 22,650  $ 14,704
  Royalties                                  975       530      2,045     1,430
  Revenue from Product Development
     Agreements                            6,808     8,113     21,182    28,092
  Revenue from License Agreements           -         -            75     3,419
  Other                                      177        95        472       283
                                        --------  --------   --------  --------
Total Revenues                            16,545    13,595     46,424    47,928

Expenses                                  28,625    22,942     86,004    67,699
                                        --------  --------   --------  --------
Net Loss from Operations                 (12,080)   (9,347)   (39,580)  (19,771)
Other Income (Expense)
  Interest Income                             62       959        635     3,049
  Equity Loss in Joint Ventures              (96)   (1,494)      (644)   (5,228)
  Other                                     (152)      806       (375)    1,443
                                        --------  --------   --------  --------
Total Other Income (Expense)                (186)      271       (384)     (736)
                                        --------  --------   --------  --------

Net Loss Before Cumulative Effect of
   Change in Accounting Principle        (12,266)   (9,076)   (39,964)  (20,507)

Cumulative Effect of Change in
   Accounting Principle                     -         -          -        2,216
                                        --------  --------   --------  --------
Net Loss                                $(12,266) $ (9,076)  $(39,964) $(18,291)
                                        ========  ========   ========  ========
Basic and Diluted Net Loss Per Share
  Before Cumulative Effect of Change
  in Accounting Principle               $   (.49) $   (.41)  $  (1.70) $   (.94)
Cumulative Effect of Change in
  Accounting Principle                  $   -     $   -      $   -     $    .10
Basic and Diluted Net Loss Per Share    $   (.49) $   (.41)  $  (1.70) $   (.84)


      While the Company has  continued to incur losses,  significant  progress
was  made  during  the   quarter   towards   the   commercialization   of  our
technologies.

      Our  100%  owned  subsidiary,   United  Solar  Ovonic,  which  is  fully
consolidated  in the 2004 results,  continued to grow its revenues and improve
its margins as it ramps up sales.  United Solar Ovonic has increased  revenues
substantially to $25.1 million and $9.2 million for the nine-


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and  three-month  periods,  respectively,  ended March 31, 2004. In April,  an
agreement  was reached  with Solar  Integrated  Technologies,  Inc., a leading
Southern  California  photovoltaic  system integration  company,  for sales of
over 5 megawatts (MW) of product for the calendar year 2004,  with  provisions
for  shipping  larger  volumes in future  years.  In  addition,  United  Solar
Ovonic also  received a 1.25 MW order from Sunset of Germany with a commitment
for another 3.5 MW in fiscal year 2005, and a 1 MW order from  ThyssenKrupp of
Germany.  Progress  was also made in United  Solar  Ovonic's  space  business.
The Air Force Research  Laboratory  selected  United Solar Ovonic to provide 3
kW of lightweight  solar cells for one of its satellites,  and Lockheed Martin
entered  into a contract  with United  Solar  Ovonic to supply solar cells for
evaluation in the U.S. government's high altitude airship program.

      Both BAE and  STMicroelectronics,  licensees  of our  41.7%-owned  joint
venture Ovonyx, have indicated they are entering a product-oriented  phase for
the Ovonic Unified Memory (OUM).

      Texaco  Ovonic  Hydrogen  Systems  (TOHS),  our 50-50 joint venture with
ChevronTexaco  Technology Ventures LLC (CTTV), received approval from the U.S.
Department of  Transportation  to transport  hydrogen in metal hydride storage
systems developed by the joint venture for portable power  applications.  TOHS
also entered into a collaborative  agreement with Dynetek Industries,  Ltd. to
design and co-develop a vessel for TOHS' metal hydride storage system.

      In a move to  reflect  the focus on the  expanding  field for our nickel
metal hydride  storage  solutions,  Texaco Ovonic Battery  Systems,  our 50-50
joint  venture with CTTV,  changed its name to COBASYS.  COBASYS has developed
a broad family of new products and, with its recently  completed  construction
of a new 170,000 sq. ft. manufacturing  facility,  is poised to take advantage
of market opportunities.

      During the quarter,  the Company's expenses for patent defense decreased
substantially  due to a lower level of activities  related to the  arbitration
with  Matsushita  Battery  Industrial  Co.,  Ltd. and related  parties.  It is
expected that the company will not incur significant  expenses associated with
the  arbitration  after  the  fourth  fiscal  quarter.   The  parties  to  the
arbitration  have requested that the Arbitral  Tribunal  postpone its decision
until July 2004 because the parties are engaged in settlement negotiations.

      The  Company is on track with its cost  initiatives  and is  identifying
additional  savings through further cost  containment  and  restructuring.  In
the near  term,  our goal is to  contain  our cash burn rate at $3  million or
less per month as we focus on  growing  revenues  and  reducing  expenses  for
substantially improved operating results.

      The  increase  in  consolidated   revenues  resulted   principally  from
increases in photovoltaic  product sales,  partially  offset by a reduction in
revenues from product  development  agreements from COBASYS, as it focuses its
resources  on  commercialization  of its  products,  as  well as  decrease  in
funding by ChevronTexaco under product  development  agreements related to the
solid hydrogen  storage  program and the elimination of funding after December
31, 2002 by ChevronTexaco of the fuel cell development program.

      Robert C. Stempel,  Chairman and CEO, said,  "While we must continue our
aggressive   actions  to   profitably   and  fully   commercialize   our  core
technologies  and  products,  we are pleased to report a 22% increase in third
quarter  revenues  from a year ago. In  particular,  we are  pleased  with the
momentum at United  Solar  Ovonic and its  significant  increase in  revenues.


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This  was due  not  only  to the  impact  of our  acquisition  of the  Bekaert
interests,  but also to increased  product sales of our superior  thin-film PV
products and their increased acceptance in the marketplace."

      The Company is engaged in a number of  negotiations  and  discussions to
fund its  operations,  including  forming new strategic  alliances to fund and
grow its  photovoltaic,  fuel cell and other  businesses and raise  additional
capital  through  equity and debt  financings.  In  addition,  the  Company is
engaged in  negotiations  with  government  agencies for contracts to fund its
development activities.

      As  of  March  31,  2004,  the  Company  had  consolidated   cash,  cash
equivalents,   short-term   investments   and  accounts  and  short-term  note
receivable  (including  $2,029,000  of amounts  due from  related  parties) of
$34,521,000,  a decrease of  $29,975,000  from June 30, 2003.  As of March 31,
2004, the Company had  consolidated  working  capital of $34,174,000  compared
with a consolidated working capital of $37,795,000 as of June 30, 2003.

      Management  believes that funds generated from operations,  new business
agreements,  equity and debt  financings,  new  government  contracts  and the
cost-containment   initiatives,   together   with   existing   cash  and  cash
equivalents,  will be  adequate to support the  Company's  operations  for the
coming  year.   However,   the  amount  and  timing  of  such  activities  are
uncertain.  Accordingly,  no  assurances  can be  given  as to the  timing  or
success of the aforementioned plans,  negotiations,  discussions and programs.
The Company has recurring  losses from  operations and is actively  engaged in
discussions to obtain the needed additional working capital.

      Additional  information  about the Company's  operations  and activities
can be found in the  Company's  Form 10-Q for the three and nine months  ended
March 31, 2004 filed with the Securities and Exchange  Commission,  which will
also be available on the Company's website on or around May 17, 2004.

      ECD will hold a conference call on Tuesday,  May 18, at 10:00 a.m. ET to
discuss  its third  quarter  fiscal  2004  results.  Access to the call may be
obtained  by  calling  1.877.858.2512  or  1-706-634-1291.  A  replay  will be
available   through  3:00  p.m.,   May  21,   2004,   at   1.800.642.1687   or
1-706-645-9291.  Callers  should  use  conference  ID#  7351192  to access the
replay.  A live webcast of the  conference  call will be  available  online at
http://www.videonewswire.com/ECDOVONICS/051804/   or  through  the   Company's
website at www.ovonic.com.

About ECD Ovonics
ECD  Ovonics  is  the  leader  in  the  synthesis  of new  materials  and  the
development of advanced  production  technology and  innovative  products.  It
has invented,  pioneered and developed enabling  technologies in the fields of
energy and information leading to new products and production  processes based
on  amorphous,  disordered  and related  materials.  ECD Ovonics'  proprietary
advanced  information  technologies  include  Ovonic  phase-change  electrical
memory,  Ovonic  phase-change  optical memory and the Ovonic Threshold Switch.
The Company's  portfolio of alternative  energy solutions  includes  thin-film
amorphous  solar  cells,  modules,  panels and  systems for  generating  solar
electric power;  NiMH batteries;  hydride storage materials capable of storing
hydrogen in the solid state for use as a feedstock  for fuel cells or internal
combustion  engines  or as an  enhancement  or  replacement  for  any  type of
hydrocarbon  fuel; and fuel cell  technology.  ECD Ovonics  designs and builds
manufacturing machinery that

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incorporates its proprietary production processes,  maintains ongoing research
and development  programs to continually improve its products and develops new
applications for its technologies.  ECD Ovonics holds the basic patents in its
fields.  More information on ECD Ovonics is available on www.ovonic.com.

                                    # # #

      This release may contain  forward-looking  statements within the meaning
of the Safe Harbor Provisions of the Private Securities  Litigation Reform Act
of 1995. Such  forward-looking  statements are based on assumptions  which ECD
Ovonics,  as of the  date of  this  release,  believes  to be  reasonable  and
appropriate.  ECD  Ovonics  cautions,  however,  that  the  actual  facts  and
conditions  that may  exist  in the  future  could  vary  materially  from the
assumed facts and conditions  upon which such  forward-looking  statements are
based.


Contacts:
--------
Stephan Zumsteg, Vice President and Chief Financial Officer
Ghazaleh Koefod, Investor Relations
Dick Thompson, Media Relations
Energy Conversion Devices, Inc.
248.293.0440


