MPB you need to factor in the cost of production into price rises and then deduct it. Pre 2005 generators did not have to pay for carbon allowances, now they do. Cost of fuel and plant components soared globally since 2005 and while they have come back they are still relatively high.
Samell yes nuclear is carbon free.... once you have built it but I suppose no one really factors in the carbon footprint of construction and yes nuclear has an extremely low production cost of about £4.5 per MWh. Nuclear is also projected to have a lower levelised cost (i.e. total cost of build and running overs its entire lifespan) than all other technologies assuming gas, coal and carbon prices do not collapse. There are a few real problems with nuclear tho,
1) Takes about 5-7 years to build once you get through all the licensing, permitting and planning.
2) Current nuclear plants are big. Westinghouses design is 1,100MW and the French EdF design is 1,600MW. The all island system is ~5,500MW at peak and half that at the lowest point.
3) Existing nuclear units do not like varying out put so if the unit is 1,100MW and you only need 800MW what do you do with the rest. That said everyone claims the new ones are flexible.
4) If a unit that size tripped in Ireland you are looking at serious security of supply problems. You need a lot of other generators sitting around with fuel stocks incase it trips.
5) I presume the new units can refuel while running but the old ones cannot and are off for months at a time.
6) The old British nuclear fleet has an availability in the 70%s while tne newer but old French fleet in the 80%s. Thats a lot of time they are not running.
7) Everybody have a view on decommissioning costs and I could make up an equally arbitrary number and give it to you but really no one knows the cost.
8) If your interested have a look at Olkiluoto 3 in Finland and Flamanville in France. They are the two European nuclear reactors EdF are currently building. Both are around 2 years behind schedule and 2 billion over budget.
The only way nuclear would work in Ireland is it we have the supergrid transmission system in place with connections to the UK, France, Spain and maybe Scandinavia.