DISTRICT COUNCIL member Mary M. Cheh (D-Ward 3) celebrated Earth Day this year by proposing a series of measures meant to lower the city’s carbon emissions. But the bill is a reminder of how unnecessarily complex the city’s anti-climate-change policy already is.

Ms. Cheh’s bill would exempt owners of local solar power infrastructure from personal property taxes on their facilities. Backers claim that the provision is necessary because companies that might want to erect solar panels on others’ property would be treated unusually harshly under the tax code. If that’s so, the council should investigate changing the law for anyone who finds himself in that bend in the tax code, not just solar developers.

As it is, solar power benefits from unfair government preferences that the council should consider repealing. The District requires utilities to derive 20 percent of their electricity from renewable sources by 2020. Though such policies are supposed to encourage competition among renewables, solar power enjoys a “carve out” within the renewable mandate, guaranteeing a piece for that particular technology unless it proves extremely expensive. If the goal is to reduce emissions, policy should instead create an environment in which the cheapest low-carbon technologies win out, not the ones politicians favor.

Ms. Cheh’s bill would also require stores to keep their doors closed while their air conditioning is switched on. Preventing such waste is obviously appealing. But the best way to lower emissions is to put a price on carbon or to set top-line goals without prescribing precisely how businesses must achieve them. This allows businesses to make their own decisions about the most efficient ways to save energy.

The fight against climate change requires government to intervene, creating incentives for cleaner energy. But in that process, it’s easy for government to get too involved in deciding how we derive and use energy. If city leaders worry that the District isn’t moving toward green energy fast enough, they should first press for a more aggressive regional carbon-pricing scheme or to modify the city’s renewables mandate.