Barbados has implemented attractive incentives geared towards increasing its renewable energy capacity to at least 29% of the total energy mix by 2029. Existing incentives include the removal of import duties for renewable energy systems and the introduction of net metering in the form of a renewable energy rider, effectively establishing compensation of up to US$0.16 per kWh for energy supplied to the grid. These changes, in addition to the rapid reduction in price of global solar photovoltaic (PV) modules – from US$4 per Wp in 2009 to under US$1 (Wp) at the end of 2014 – have resulted in a considerable increase in PV installations on the island. Grid-connected solar PV installed capacity has risen from zero in 2009 to over 7MWp by the end of 2014. As installations continue to increase, there is a need to fully understand the effect of the Caribbean’s unique environment on PV performance. Barbados, the easternmost island in the Caribbean, has a strong solar irradiance with 'cooling' winds, and is a good environment for PV utilisation. However, as dust concentrations in the atmosphere vary, so will their accumulation rates onto module surfaces and hence the irradiance received by the cells. Dust accumulation rates are increased by lower tilt angles and increased relative humidity. Rainfall and wind are considered good natural methods for cleaning module surfaces, however they are only effective during intense showers and high winds. In addition, the properties of the dust determine the rate of accumulation based on the ability of dust particles to stick to the module surface. In this paper, we describe the effect of dust accumulation on four types of PV modules installed at three sites in Barbados – designated as urban, suburban and rural-coastal sites. Crystalline silicon modules were connected separately across resistors and the power output obtained at each site. The power output for April 2015 is described, including a period before and after cleaning.