The most efficient solar cells today are concentrating multi-junction photovoltaic (PV) cells. However, a higher efficiency and more flexible system can be made by using spectrally-split PV or direct energy conversion (DEC) solar cells. The DEC cell can function as a dipole, bowtie or ring nano-antenna with frequency down conversion or rectifying. A process, pioneered by WETC, could safely convert nuclear waste into energy. The process, involving a fuel cycle without uranium enrichment and plutonium isolation, would avoid keeping the gaseous fission fragments restrained in DEC-type fuel elements, an innovative strategy used to control a reactor.

While the clean energy source with current densities close to the field emission limit is our main goal, our present are a human retina-type detector and medical isotope production unit driven by an accelerator with post-acceleration. The unit that almost-entirely eliminates the waste byproduct and plutonium proliferation can serve as a power or propulsion system prototype.

The Lorentz theory could play a great role in the environmentally-friendly development of radiation, solar and electrical-in-nature nuclear energy. A long time before quantum mechanics, Lorentz suggested that some disturbances, like waves, could be transmitted with traveling particles through the vacuum without moving it. At that time, instead of careful analysis of the systematic errors, some scientists chose to postulate constancy of the light velocity to explain why the earth appears not to rotate around the sun in the Michelson experiment. Mathematically, it was based on the Lorentz transformations. As they equally apply to any wave motion, the anisotropic values of the velocity of light are used in Einstein's original manuscript and all applications. Field equations of general relativity do not lead to attraction between material bodies and the small spectral line shifts in enormous fields of dense stars challenge the principle of equivalence of gravity and acceleration.

The Lorentz metric is associated with the non-propagation waves. These waves that satisfy the Klein-Gordon equation also occur in the vacuum filled with virtual particle-antiparticle pairs. Here, a cutoff frequency ?c =mc2/ , where h is Planck's constant and mc2 equals the sum of the kinetic, internal and potential energies associated with a test particle. The fundamental constants are determined from the simple model of pairs reacting like forced linear harmonic oscillator.

Lorentz was ahead of his time and his approach led to the natural introduction of the field values (group velocity and intensity of de Broglie waves) into Maxwell's equations, and antimatter (antiparticles or modes with negative group velocity) into Newtonian mechanics. Antiparticles are attracted by ordinary matter, but repulse ordinary matter and each other gravitationally. This interaction could lead to the universe expansion and maintain the energy reservoir for cosmic sources of intense radiation. The transformation from the Coulomb gauge (instantaneous scalar potential) to the Lorentz gauge results in retarded solutions for both transverse electromagnetic and longitudinal gravitational vector potentials proportional to their scalar potentials (see http://arxiv.org/abs/physics/0401017).