Complex sentence: A report by Lord Weir led to The Electricity (Supply) Act 1926 (repealed 1989), which created the Central Electricity Board and the National Grid operating at 132 kV (50 Hz).
Split into simpler sentences: A report by Lord Weir led to The Electricity (Supply) Act 1926 (repealed 1989). This Act created the Central Electricity Board and the National Grid operating at 132 kV (50 Hz).