Cornerstone Sustainable Energy Enters Into First Geothermal Project Development Agreement

To be located at the Surprise Valley Hot Springs in Cedarville, California.

NEW YORK, July 1, 2013 -- Cornerstone Sustainable Energy

("CSE"), (OTCBB:RCVA), has entered into an agreement with Warner Mountain
Energy Corporation to begin the first phase of development of a geothermal
energy plant to be located at the Surprise Valley Hot Springs in Cedarville,
California. This phase of development will include a feasibility analysis,
conceptual design, and budgeting to install CSE's PwrCor engine with
required site infrastructure to generate electrical power. The electricity
generated would be entirely "green". This would be the first installation
using the PwrCor engine to generate electricity by using heat from a
geothermal resource.

Warner Mountain Energy owns or controls approximately 1000 acres at the
Surprise Valley Hot Springs. The site has several artesian hot springs free
flowing to the surface, delivering an aggregate of approximately
850 gallons per minute at 205 degrees F. CSE will tap the hot spring water
to supply heat to its PwrCor engine. CSE's technology is projected to
produce 250 kilowatts of electric power with 150 gallons per minute of water
at 180 degrees F. At that level of output, the Surprise Valley Hot Springs
site represents a potential estimated at
1.5 megawatts of constant, uninterrupted electric power.

Once online, the PwrCor engine operates at input temperatures and flows that
are considerably less than those required by competing technologies. The
ability to operate at these lower temperature and flows enables geothermal
developers to exploit resources that were previously unusable for the
commercial production of electricity. The impact to the geothermal industry
could be significant.

About Cornerstone Sustainable Energy, Inc.

CSE is a cleantech company focused on energy infrastructure development
projects and delivering alternative energy solutions to a wide range of
commercial and not-for-profit customers.

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