Conventional wisdom has held that electrolyzing hydrogen is too expensive largely due to the cost of electricity as an input.  That has changed in certain contexts and is set to change broadly.  According to an July 5, 2017 article in Carbon Commentary:

“Generating an extra unit of electricity via PV or wind has no cost. One implication of the growth of renewables is that open-market power prices will therefore tend to fall. As the economists say, prices tend to converge on the marginal cost of production. We are seeing this today in electricity markets. This has profound effects.”