Author: 
Mikael Axelsson
  • 2020-05-29
  • 11 MIN READ
2020-05-29
Author:
Mikael Axelsson
11 MIN READ

Why Garantell Chose Thermal Energy

There is no doubt that climate change is shaping our history. Each and every one of us must take action to lighten the load on our planet. For an individual company, however, finding ways to make a real difference may seem challenging.

Everything we need to heat and cool our properties and/or processes can be found in the ground directly beneath out feet. It’s called thermal energy; heat from the sun stored in bedrock which we are able to use. The best thing about it is that it’s renewable, carbon-free, and natural.

How thermal energy works

Solar energy is stored in bedrock in the form of thermal energy.

Thermal energy can be harnessed by using a ground source heat pump to make use of the meagre heat stored in bedrock and augmenting it with compressors and heat exchangers.

A ground source heat pump works according to the same principles governing fridges. The goal is to move heat from the pump cabinet to the indoor air. The heat pump transfers heat from the bedrock to the building’s waterborne heating system.

Cool all year round

To extract thermal energy, a hole is bored into the bedrock into which fluid-filled collector coils are sunk, which then convey the heat to the heat pump. This fluid maintains a temperature around 0 °C in the spring and rises to, at most, around 6 °C in the autumn.

This means it is cool all year round, which is used for free cooling. In addition to being conveyed to the heat pump, the collector fluid can also be sent to a cooling system. Generating cooling from the bedrock in the summer increases the temperature of the bedrock, which enables greater efficiency of the ground source heat pump during the winter heating period.

Production at Garantell

Production at Garantell largely involves spot welding, a type of resistance welding used to weld sheet metal and wires. Two electrodes, usually copper, clamp the sheets and wires and forces a current through them. As a result, the material melts and forms a weld at a ‘spot’. This process generates a lot of excess heat in electrodes, current conductors and transformers. And this heat must therefore be dissipated.

Free cooling from bedrock

The heat is dissipated via fluid conduits in the welding equipment through which the coolant circulates. This fluid is then conveyed through a 1.2 km long pipe (12 x 200 m boreholes) in the bedrock. In addition to cooling the welding equipment, the production facilities are also cooled during the summer by means of a cooling coil in the ventilation system. This cooling is also generated from the bedrock. The only energy supplied is the electricity in the circulator pumps which pump the coolant around.

Previously, cooling systems with very high energy consumption were used.

Four times more energy

In the winter, the production facilities and large sections of the warehouse are heated by large heat pumps that are also connected to the same bedrock, but here we make use of the heat instead: the stored solar energy and the stored energy from the coolant. The heat pumps provide about four times more energy than the energy we produce with electricity, so this has been very beneficial in terms of our environmental efforts.

The electricity we buy is 100% renewable (hydropower and wind power).

Garantell makes a difference

This is a way for us to make a difference, to lighten the load on our planet. The most eco-friendly electricity is electricity that has never been produced. Saving electricity is an important environmental measure, and it’s all about getting the most use out of as little valuable electricity as possible.

Share