CREATE TABLE nuclear_power_plants (id CLOB, name CLOB, latitude CLOB, longitude CLOB, country CLOB, status CLOB, reactortype CLOB, reactormodel CLOB, constructionstartat CLOB, operationalfrom CLOB, operationalto CLOB, capacity CLOB, lastupdatedat CLOB, source CLOB)

Which reactor type has the largest average capacity?
SELECT reactortype FROM nuclear_power_plants GROUP BY reactortype ORDER BY AVG(capacity) DESC LIMIT 1
SELECT "reactortype" FROM "nuclear_power_plants" GROUP BY "reactortype" ORDER BY AVG("capacity") DESC FETCH FIRST 1 ROWS ONLY