Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_143352_1 (construction_started VARCHAR, agr_power_station VARCHAR)
### Question:
What year did construction start at Heysham 1
### Answer:
SELECT construction_started FROM table_143352_1 WHERE agr_power_station = "Heysham 1"