Ofgem has started an investigation into "alleged behaviour" of some windfarm operators.
The National Grid currently pays windfarm operators to switch off their turbines when generation outstrips demand to prevent an overload on the grid.
The amount an operator gets paid is based on how much energy a company says it will produce should the turbines be left on.
However, analysis from Bloomberg found 40 of 121 windfarms studied overstated their output by 10% or more, while 27 by 20% or more.
Angus MacNeil, chairman of the Commons energy security and net zero committee, said: "There should be algorithms and AI that can quickly predict this more accurately, instead of just taking what those wind farms themselves say they can produce. There is no checking mechanism and there should be a checking mechanism."
National Grid has said £19m will be allocated to infrastructure improvements in 2025/26.