The goal of the ELMO Bumpy Torus Reactor (EBTR) study is the evaluation of the EBT confinement concept as the basis for development of a commercial fusion power reactor. A multidisciplinary, self-consistent treatment of EBT reactor scaling and design has been completed and a reference design (EBTR-48) has been developed. This design, based on a realistic plasma model and relatively conservative engineering parameters (i.e., 1 MW/m/sup 2/ neutron wall loading and a 7.3 T maximum toroidal field), is a steady state, ignited-mode system with high plasma power density and aspect ratio. The total thermal power of EBTR-48, exclusive of blanket multiplication, is 4000 MW; the design is based on a standard module and the design power level for a particular plant is determined by the number of modules used. Several design variants have been investigated in detail to illustrate the effect of near-term and advanced technologies and to illustrate the design freedom offered by devices with low field and high aspect ratio. The high aspect ratio simplifies many aspects of the design, most notably those associated with remote maintenance, accessibility, and repair. It appears that a commercially successful EBTR could be constructed with only slight advances in existing technology, ifmore » the present understanding of the physics can be extrapolated to the reactor regime and does not differ markedly from the model developed for this study.« less