The term "energy" is a fundamental property of everything in the universe.
According to scientist Albert Einstein, energy and mass (matter) can interchange. Everything has some form of energy. Whether it is heat, nuclear, magnetic or electrical energy.
Another natural law states that energy cannot be destroyed or disappear. It is simply transformed into another type of energy (or substance).

Our bodies can feel certain kinds of energy. For instance as heat. We cannot feel all types of energy. Eg. radioactive energy. For such purposes, special measuring devices have been developed.

Within the paranormal world, a special kind of  "spiritual energy" exists. It cannot be measured and is felt very individual. It is alleged that clairvoyants in particular, are able to detect these energetic phenomena.

It is believed that the paranormal  has some form of unknown energy. The problem in measuring these energies, is no device can measure "unknown energy". Therefore, you see a host of ​​- more or less - serious devices to register the paranormal.
The property of an energy can always be measured by some form of suitable tool. If the energy cannot be traced in this way, one can by definition not make a scientific measurement of the energy. Therefore, it cannot be confirmed in its measurability.

In this case, many choose to call the energy "spritual", as one does not have to relate to units, measurement units and evidence. This gives the word energy a very individual  tone.

Lightning can generate over 2 million Volts and 60.000 Amperes. / WikiPedia / Public Domain