WASHINGTON — A conservation group gave U.S. Sen. Daniel Akaka top scores in the Hawai'i congressional delegation for his votes this year on environmental and clean-energy legislation.

Akaka, D-Hawai'i, scored 100 percent in the rankings released Friday by the League of Conservation Voters.

He voted with the league's position on 11 Senate votes that included clean-energy tax credits, global warming pollution reductions, low-income energy assistance and public lands protection.

"In Hawai'i, we know our environment is one of our most valuable and most fragile resources," Akaka said. "I was proud in this Congress to support legislation, now law, that provided the first increase in fuel-efficiency standards in decades and set ambitious standards for renewable fuels grown in the U.S."

Sen. Daniel K. Inouye, D-Hawai'i, scored 91 percent in the rankings. He didn't vote against any of the league's positions but had points subtracted for missing the vote on the low-income energy assistance bill.

In its House rankings, the league — a national, nonpartisan group that supports pro-environmental lawmakers — used 13 votes on issues ranging from clean-energy tax credits to oil and gas drilling.

Rep. Mazie Hirono, D-Hawai'i, did not oppose any of the league's positions but scored 92 percent because she missed a vote on legislation to increase oil and gas drilling.

Rep. Neil Abercrombie, D-Hawai'i, had the lowest score in the delegation at 77 percent. Abercrombie missed two votes and voted against legislation barring federal payments for crops planted on some lands. The aim of the legislation was to reduce incentives for converting native prairie to crop production.