Grid parity

Paper on how this is a very contested/fuzzy term

L.A. Hurtado Munoz ⁎, J.C.C.M. Huijben, B. Verhees, G.P.J. Verbong  (2014)  The power of grid parity: A discursive approach.  Technological Forecasting & Social Change Vol. 87, pp.179–190.