Lake Erie is the fourth largest, in surface area, of the Great Lakes. Seiching events in the lake have in the past led to breaches of the flood wall in Buffalo (at the eastern end of the lake), causing loss of life, and significant loss to properties. Here, we analyze the potential of Lake Erie for generating electricity from its storm surge, seiching, and wave energy resources. We find that there is significant potential energy in the lake that may be suitable for generating meaningful levels of electricity from seiches and storm surge; for instance, by developing an artificial ‘lagoon’. It is shown that an extreme surge event similar to that of January 30, 2008 which generated a surge of approximately +3 m at the eastern end and a corresponding set-down of nearly −2.7 m at the western end of Lake Erie, could contain a total theoretical potential energy of approximately 5 × 107 kWh. If such energy could, practically, be harnessed using a surge lagoon with a surface area of 2 km2 near Buffalo, the potential energy would be 2.3 × 104 kWh, enough energy to power the equivalent of 40 homes for an entire month. The cost of such a lagoon could be partially offset by the potential of such a structure, and the operation of such a lagoon, to help alleviate flooding during extreme events. Furthermore, as an example, the analysis of the lake-wide wave data for 2011 shows that the monthly mean wave power is greater in the central and eastern basins of Lake Erie. Wave power was highest in October and November when the monthly mean wave power reached 10 kW/m. In contrast to most oceanographic environments, the wave power resource is reduced in winter, mostly due to the presence of surface ice in the lake. The surface ice appears to significantly reduce wave height and power during winter months, resulting in a relatively low annual mean wave power. However, the monthly mean wave power was the lowest in late spring and during summer when the monthly mean wave power was around 2.5 kW/m. Although this study represents the first attempt to assess the marine renewable energy of Lake Erie, further research is necessary to examine the feasibility of energy extraction in the lake.