Enhanced Salience of Nonlinear Pricing and Energy Conservation

Digital tools hold promise for scaling energy conservation by giving households real-time information about their electricity use and costs. Yet whether such app-based interventions can meaningfully reduce consumption depends on users’ engagement. We conduct a natural field experiment on a random sample of 45,000 electricity customers in Hanoi, Vietnam, that tested two mobile-app interventions built on the utility’s smart-meter platform. One treatment (“price salience”) displayed each household’s current marginal price tier and consumption to date; the other (“billing salience”) showed consumption and bill to date. Across the full sample, neither intervention reduced electricity use on average, and we can rule out effects as small as one percent. To understand this precise null, we examine engagement with the app and find no effects on the extensive margin, and only limited responses on the intensive margin. Among households that already engage with the app, the price-salience treatment modestly increased engagement and led to small consumption declines late in the billing cycle, when marginal prices rise mechanically under the nonlinear tariff. These results underscore both the promise and limits of digital behavioral tools for demand management -- while low-cost app integrations can inform attentive users, engagement does not necessarily scale with delivery, limiting the ability of such interventions to automatically generate population-level energy savings.