An Analysis of Water, Energy and Food Nexus: A linear and Nonlinear Granger Causality Approach

Abstract

The nexus between water, energy and food security has drawn attention among researchers and policymakers in recent times. Given that empirical works in the area are scanty, this paper empirically evaluates the water, energy and food security (WEF) relationship using both linear and non-linear Granger causality approach. By employing data for five (5) selected African countries, the results from the linear estimations showed mixed causality between the key variables (Water, Energy, and Food). Evidence of a non-linear causal relationship between the variables was not found because the estimates obtained were predominantly statistically insignificant. The findings of the study indicate the presence of unidirectional linear causality running from Water to Energy, which was found for three countries (Egypt, Nigeria, and South Africa). The study also found the presence of causality running from water to food in South Africa. On the other hand, no evidence of causality between energy and food was found.