Households' willingness to pay for substituting natural gas with renewable methane: A contingent valuation experiment in south korea

South Korea is planning to substitute some residential natural gas (NG), a fossil fuel that relies on imports, with renewable methane (RM) from bio-gas, a renewable energy source. Thus, information about households' willingness to pay (WTP) for implementing the plan is widely needed. This article, therefore, examines the WTP using an economic approach of contingent valuation (CV). More specifically, 1000 households were asked about the additional WTP for RM over NG through in-person face-to-face surveys across the country, adopting a dichotomous choice question format, during August 2018. As a few interviewees responded zero WTP for various reasons, a spike model that could reflect zero WTP observations was utilized. The household additional WTP for RM over NG was estimated, with statistical significance, as 191.46 Korean won (USD 0.17) per m3 and worth 31.9% of the average price of residential NG. This value means a price premium for RM compared to NG. In other words, this study found that South Korean consumers value residential RM about 1.32 times as much as residential NG. These results from the CV experiment could be a useful reference in establishing and implementing RM-related policies.