A NUCLEAR-PHOTON ENERGY CONVERSION STUDY
Abstract
A double energy conversion technique was studied for aerospace use as a radioisotope powered 10 watt electrical output power source. In this technique, beta particles from a radioisotope are absorbed by a luminescent material which emits a multiplicity of low energy photons. These photons are then converted to electrical energy by a photovoltaic device. The three components (radioisotope, phosphor, and photovoltaic cell) are discussed individually and then in combina tion in various geometries of source-phosphor and phosphor-photovoltaic converter. Nuclear radiation effects on the phosphor and photovoltaic materials restrict the choice of the radioisotope to a low energy beta emitter; and temperature ef fects limit the number of unit power cells which may be stacked in one bundle. These effects are more pronounced in silicon photovoltaic converters than in ZnCdS: Cu type phosphors. A ten watt output power source fabricated with currently available materials (Pm-147, ZnCdS: Cu, and sili con photovoltaic cells) would have an overall energy conversion efficiency of about 0.2 percent and a power per weight ratio of 4 mw/lb. It is estimated that the power per weight could be in creased by a factor of ten to forty if certain ideal materials were available. The rapid decrease in photo voltage and energy conversion ef ficiency of silicon cells at low illumination in tensities causes an appreciable loss in the over all efficiency of such power source.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1963
- Accession Number
- AD0402695
Entities
People
- H. V. Watts
- M. D. Oestreich
- R. J. Robinson
Organizations
- IIT Research Institute