SELECT AVG("2400 kWh/kW p y") FROM table_41665 WHERE "1400 kWh/kW p y" > '12.9' AND "1200 kWh/kW p y" > '21.7' AND "1600 kWh/kW p y" > '18.8'
What is the average 2400 kwh/kw p y with a 1400 kwh/kw p y greater than 12.9, a 1200 kwh/kw p y greater than 21.7, and a 1600 kwh/kw p y greater than 18.8?
CREATE TABLE table_41665 (
    "20 years" text,
    "2400 kWh/kW p y" real,
    "2200 kWh/kW p y" real,
    "2000 kWh/kW p y" real,
    "1800 kWh/kW p y" real,
    "1600 kWh/kW p y" real,
    "1400 kWh/kW p y" real,
    "1200 kWh/kW p y" real,
    "1000 kWh/kW p y" real,
    "800 kWh/kW p y" real
)