The Government has said the amount of money retail investors will pay for the shares will be capped and will not go up even if the value of the shares goes up during the 18 months.
That means if the value of the company goes up during that time investors are on to a winner.
But on the downside the value of the company could also go down.
That is a very real risk given the general election is due to take place in the second half of next year, before the final payment for Meridian is due.
If Labour and the Greens are voted in the intention is to change the entire way the market is regulated using a single buyer model where an agency would be set up to pay generators a price which reflects the cost of their power production.
Meridian would be a big loser under that model as most of its production comes via water and wind - two very low cost ways to produce power.
The value of Meridian could fall dramatically if that were to happen meaning investors could end up overpaying for the shares through the final instalment.
Of course investors can sell their shares anytime before the last payment is due as Meridian will be listed on the stock market.
It's all about weighing up the risks - unfortunately it's not something retail investors have been very good at in the past.