Our partner for pwer plants: The Green Energy AG

The Green Energy AG is one of Germany's leading geothermal energy groups.

Founded in Hanover in 2002, Green Energy is a pioneer in the young geothermal energy industry, and it is the first industry provider of geothermal funds and subscription bonds. Green Energy AG, based in Hanover, is at the head of the international AG, which has 3 locations in Germany and the USA.

The Green Energy AG, with its subsidiaries and investment companies, incorporates the entire range of strategic, technical and operative expertise needed for success in the field of deep geothermal energy and offers profitable financial products for environmentally and profit-oriented investors.

Core Activities of the Green Energy AG

Geothermal Power Plants: Planning, implementation and operation Strategic Participations: Pioneer in the geothermal energy growth industry Geothermal Financial Products: Invest in climate protection, increase capital

Green Energy plans to build highly efficient, environmentally friendly power plants at Germany's best geothermal sites. Construction commences as soon as exploration and drilling work has been completed. Green Energy geothermal power plants are designed for production of 6 MW, about the electricity consumption of a small town with a population of 30,000 inhabitants.

The above-ground power plant will take around eleven months to build and will fit perfectly into its surroundings thanks to ambitious, ingeniously low-key architectural designs. A Green Energy power plant doesn't take up much space; the entire plant will cover an area comparable to the space needed by a small gymnasium.

Exploration with One Goal: Heat!

Using selected geological data, Green Energy has developed the Green Energy Exploration Navigator (GREEN). This gives Green Energy a state-of-the-art modelling tool that makes choosing the best possible geothermal site a lot easier and more effective than before.

For precise site inspection, Green Energy has purchased the data a number of major oil companies gathered during their oil and gas exploration projects. The data contains the results of two-dimensional seismic explorations and test wells. Green Energy has fed this data into state-of-the-art software to produce model calculations that give us essential initial orientation in the ground.

To find the exact position for the power plants and, most importantly, to develop an economically feasible drilling strategy, we examine the ground conditions with a geological "magnifying glass": 3-D seismic imaging. Two dimensional seismic data only provides information along a line, while 3-D seismic imaging – combined with mathematical simulation models – provides high resolution, three-dimensional images of underground cubes. The simulation models also let us take a look into the future: The geologists place the power plant in the model at a favourable position and then simulate what happens in the ground when the plant is in operation.

Intelligent Drilling Strategy, Innovative Technology

The geothermal exploration phase comprises 3-D seismic evaluations, assessments of the infrastructure, and of all prevailing technical and legal conditions. As soon as the exploration phase has been positively concluded, drilling can begin.

This is a decisive phase of the project: The first well shows whether the water is actually hot enough and whether capacity is adequate – in other words, whether sufficient water can flow through the rock. Depending on the depth and type of well, this requires an investment of between seven and nine million euros.

An intelligent drilling strategy vastly increases the chances of profitable operations. We work with proven technology similar to that used in gas and oil wells. A location cannot always be reached by drilling vertically, in which case we use directional drilling to drill "around the corner".

This drilling technology is ideal for geothermal energy. It allows the geologists to drill several wells from one central location and create branches – like a fir tree. Tapping a well from several sides in this way can vastly increase the productiveness of the heat source and optimise the power plant yield right from the outset. From the very start, Green Energy ensures that only top international drilling technology is used at its sites.

Power Plants: Full Steam Ahead for Highest Electricity Yield
power plant
		In the geothermal power plant, the maximum amount of heat is withdrawn from hot water from the depths of the earth using heat exchangers designed to generate as much steam as possible. The trick is in the heat exchanger, where the hot water releases its heat to another heat transfer medium. This environmentally friendly "working medium" boils at 30°C (86°F) which means that it generates more steam and produces a high electricity yield. Choosing the right medium is very important when it comes to optimising the fluid cycle and efficiency.
Heat Exchange
heat exchang process
		There are currently two different processes available for the induction of heat by means of exchange processes: The ORC and Kalina technologies. In the ORC method, a medium with a fixed boiling point is used, while Kalina technology uses a medium with a flexible boiling point (a mixture of ammonia and water). The Kalina method is relatively new, while ORC technology has been around for a long time. It has been used for around 40 years in industrial processes to convert waste heat from production processes into electricity. Because ORC draws on tried and tested procedures and technooogy, Green Energy has decided to deploy the ORC process in its power plants.