Houston may be the energy capital of the world, but it apparently isn't the capital of "greenness."

The Bayou City lands at No. 93 among the 100 largest U.S. cities in a new WalletHub ranking of the country's greenest places. Houston held the same spot in last year's ranking. Aside from being the eighth worst city in the 2021 study, Houston is the lowest-ranked city in Texas.

To determine the cities promoting an environmentally friendly lifestyle, WalletHub compared the 100 largest cities across 28 key "green" indicators. Those factors include greenhouse gas emissions per capita, number of smart energy policies and initiatives, and green job opportunities.

Unfortunately, Houston's overall showing isn't impressive. Here is a sampling, with No. 1 being best, No. 50 being average, and No. 100 being worst:

• Excess fuel consumption per year, No. 97.
• Greenhouse gas emissions per capita, No. 94. Houston tied with five other cities for the worst greenhouse gas emissions.
• Median air quality index, No. 72.
• Share of commuters who drive, No. 54.
• Percentage of green space, No. 37.
• Farmers markets per capita, No. 35.
• Walkability, No. 34.

Here is how other Texas cities fared:

• Austin, No. 26.
• Garland, No. 44.
• San Antonio, No. 46
• Laredo, No. 68.
• El Paso, No. 69.
• Irving, No. 74.
• Plano, No. 79.
• Lubbock, No. 83.
• Arlington, No. 85.
• Dallas, No. 89.
• Corpus Christi, No. 90.

San Diego tops the WalletHub list.As Houston hangs out toward the bottom of the WalletHub ranking, government and business leaders in the region are striving to make Houston greener.

For instance, the City of Houston in August launched a pilot project that will speed up the permitting process for environmentally friendly stormwater projects.

And just this month, Houston Mayor Sylvester Turner declared October 6 as Energy Efficiency Day. The occasion encouraged residents and businesses to support the city's clean energy goals. "Implementing energy efficiency measures is the cheapest, fastest, and cleanest way to reduce Houston's energy demand," the mayor's office says.

In a news release, Laura Patiño, the city's interim chief resilience officer, says Houston must come up with solutions to combat climate change, ensure a "just and equitable" transition to clean energy, and "promote economic growth in an inclusive and transparent manner."

Despite the poor performance in the WalletHub study, Houston continues to make headway in green energy.

For example, Turner in August touted Houston's status as the No. 1 municipal entity in the U.S. for the most annual consumption of power from renewable sources. The U.S. Environmental Protection Agency (EPA) list features participants in its Green Energy Partnership.

In a news release, Turner said the EPA recognition is "great news for the city of Houston and, by extension, for the rest of the world. We are going big to set the example for cities around the world. If 100 percent renewable energy can happen in Houston, it can happen in any other city."