Highly efficient direct current appliances have the potential to dramatically increase the affordability of off-grid solar power systems used for rural electrification in developing countries by reducing the size of the systems required. And, price declines and efficiency advances in light emitting diode (LED) technology are enabling rapidly increased use of small off-grid lighting systems in Africa and Asia, according to the authors of this report. They argue similar progress is also possible for larger household-scale solar home systems that power appliances such as lights, TVs, fans, radios and mobile phones. Though their results vary according to the appliances used with the system, the authors found that the total cost of solar home systems and their associated appliances can be reduced by as much as 50% when super-efficient appliances are used. However, policy and market support are needed to realize rapid adoption of super-efficient appliances.