CLIENT NAME: Energiewende Garching (EWG, “Energy Turnaround for and in Garching”) SEGMENT: Power generation

1. VACON CASE STUDY ENERGY FROM THE EARTH
www.vacon.com1
Photo courtesy of STX Europe
ENERGY FROM THE EARTH
CLIENT NAME: Energiewende Garching
(EWG, “Energy Turnaround for and in Garching”)
SEGMENT: Power generation
PRODUCTS USED: VACON®
NXC
LOCATION: Garching municipality near Munich, Germany
Photo iStockphoto/Asergieiev and Vacon

2. VACON CASE STUDY ENERGY FROM THE EARTH
www.vacon.com2
KEY FACTS OF CLIENT:
• The name Energiewende Garching (EWG, “Energy
Turnaround for and in Garching”) is a name for the operators,
the Municipality of Garching and Bayernwerk AG, the largest
energy provider in the region, which both have a 50% holding
in EWG. It is also a program that is accepted as an ongoing
commitment and is carried out in a spirit of climate and
environmental protection, aiming at the sustainable provision
of energy needs.

3. VACON CASE STUDY ENERGY FROM THE EARTH
www.vacon.com3
CHALLENGE:
• Some 99% of planet Earth has a temperature of more
than 1000 degrees Celsius. This heat is used in geothermal
processes.
• To ensure a sustainable, regenerative supply of district heat
to Garching, a hydrothermal system is used that accesses hot,
underground water resources.

4. VACON CASE STUDY ENERGY FROM THE EARTH
www.vacon.com4
CHALLENGE:
• The hydrothermal heat energy for Garching is obtained from
the TH2 geothermal borehole at a depth of around 2000 m.
After heat extraction, the water is returned through the TH1
return borehole to the grey limestone groundwater strata
from which it originates, at a depth of 2000 m. The process
engineering involved designing and constructing a
pressurization system to ensure that the entire heat recovery
system (from extraction borehole to return borehole) is kept
under pressure in order to reliably prevent outgassing from
the hot water.

5. VACON CASE STUDY ENERGY FROM THE EARTH
www.vacon.com5
CHALLENGE:
• Natural pressure only raises the hot water to around 110
meters below ground level, so the water, with a temperature
of 74°C, is pumped to the surface by a submerged centrifugal
pump. This pump is 18 m long and is suspended in the
borehole at a depth of 340 m. From the outside the submerged
centrifugal geothermal water pump appears to be just a long,
slim metal tube, but inside it is packed with state-of-the art
technology designed for many years of service under extreme
conditions. >>

6. VACON CASE STUDY ENERGY FROM THE EARTH
www.vacon.com6
CHALLENGE:
The pump can achieve a volume flow up to a maximum of
100 liters per second. With a top temperature of 74°C at the
extraction borehole, the geothermal energy circuit provides
a usable heat content of up to 8 MW (approx. 192 MW hours a
day). The pump is located beneath a garage-sized building on
the drilling site that also houses the end of the extraction pipe
leading to the surface. The feed pump power supply is located in
another building on the TH2 drilling site.

7. VACON CASE STUDY ENERGY FROM THE EARTH
www.vacon.com7
SOLUTION:
• The heart of the extraction system is the
motor that drives the underground
extraction pump; this is supplied by a
12-pulse AC drive with an integrated
sinus filter in the output that allows the
speed to be controlled between 39 and
57 Hz. An enclosed VACON NXC AC
drive was chosen because of its
exceptional performance characteristics.

8. VACON CASE STUDY ENERGY FROM THE EARTH
www.vacon.com8
SOLUTION:
• The AC drives from Vacon are compact and have been
extensively tested for use under tough operating conditions.
They are generally used in the mining, oil, gas, water and
waste water treatment industries. The excellent thermal
properties of the enclosure ensure that the AC drive has a
long life and trouble-free operation, even in harsh conditions.

9. VACON CASE STUDY ENERGY FROM THE EARTH
www.vacon.com9
TESTIMONIAL:
“Our aim is to supply as many people, businesses and institutions
as possible with clean district heat.”
Michael Weng
Managing Director of Energiewende Garching
FOR FULL STORY:
http://www.vacon.com/Vacon/media/References/Energy-from-the-earth/