System Approach

Here is presented two approaches to materialize ZPE harvesting. (Note, LENR (Low Energy Nuclear Reactions) is not ZPE)

Vacuum tube approach is about extracting zero point energy by electrons at relativistic velocities. A burst of electrons is discharged in a vacuum tube and accelerated by voltage difference of cathode and anode. Short burst of electrons at high dV/dt interact with ZP virtual particles. Interaction means reactions enabling tunneling that end as photons that are converted to electricity in a PV cell. This approach has the advantage of opening for development using well known vacuum tube and discharge tube technology. 

EVO (Exotic Vacuum Object) approach is based on deep insights of quantum physics where particles may tunnel from false vacuum to true vacuum. The tunneling result in formation of Exotic Vacuum Objects (EVO), Bose-Einstein condensate (BEC), negative energy and negative mass. This approach have some support from known quantum systems and real life observations like the Ken Shoulder's experiments and experiments at CERN. Transmutation is a common problem in these systems which destruct the materials and shorten the lifetime of the device. 

This discharge tube is not too different from a regular gas filled HID lamp  used as head lights in cars. It is believed that this approach was chosen by Andrea Rossi when he did a live demonstration in Stockholm in 2019 (E-Cat SK) showing a tube with light emissions. Transmutation problems may be solved when reactions take place in the void space of the tube avoiding contact with materials prone to transmutation. The absence of transmutation is supported by E-Cat predicted lifetime 100,000 hours.