This paper presents the photovoltaic technology, the world’s market trends in the past few years and its future map till 2050. The paper shows the PV market development in the world in terms of cumulative installed PV capacity from 2000 to 2013 as actual PV installation in all the world in terms of total installed PV capacity (135GW), annual installed PV capacity (37GW) and PV electricity energy generated in each year. According to the forecast of global PV generation, China is expected to be the largest producer of PV electricity soon after 2020. By contrast, the United States’ share is expected to remain at about 15% starting 2020 onwards, while Europe’s share is expected to decrease constantly from 2015 to 2045. The paper also shows that almost all of the energy consumption in Egypt was met by oil and natural gas at 41% and 46% respectively. The remainder was supplied by coal and renewable energy sources. The current demand forecast expects a six percent demand growth per year over the next seven years. Egyptian Electric Holding Company is currently implementing new generation projects to produce 7000MW over the next few years. For the purpose of designing and sizing PV systems the paper presents the five relevant economic methods of financial analysis that are often used for making building investment decisions. These methods are payback analysis, net benefit analysis, saving-to-investment ratio, adjusted internal rate of return and life-cycle cost. In the same manner, the paper presents two case studies of the financial assessment analyzing PV systems in Egypt. The first case is relates to the on-grid PV 10MW power plant for different sites, while the second paper describes the finance analysis of a standalone off-grid PV system generating electricity to feed a residential house in rural area of Egypt.