The most important Government Bills usually start in the House of Commons and then come to the Lords.

But the Climate Change Bill has started with us.

It's about setting targets for reducing carbon (and therefore greenhouse gas) emissions up to 2050.

It's about national carbon targets and budgeting, and setting up an expert Committee of Climate Change to oversee all this.

And it's already started its line by line examination in a committee of the whole House.

But when we get to Part 5 we'll suddenly descend from the possibly sublime to the apparently ridiculous as the Bill plunges into the back street world of council refuse collection.

Since I deal with both environment and local government matters for the Liberal Democrats, I've got the job of tackling this part of the Bill!

This is the Government's plan for the infamous "pay as you throw" schemes in which households which throw away more "residual waste" - the stuff that's not recycled - will be charged more.

There are several ideas for doing this. You could get a council tax rebate if you have a smaller bin.

Or they could weigh the bins as they are emptied - you pay more if you throw away more or get a rebate if you throw away less. (This might be done using silicon chips embedded in wheelie bins - the so-called "chip and bin"!) You could pay more for extra collections, say once a week instead of every fortnight. Or a fourth way might be to sell sacks and charge for one that is used.

I don't think these schemes are the best way to reduce waste. If councils provide really good recycling schemes (including for kitchen waste) they will get the results without all the problems and bureaucracy of "pay as you throw".

The job of the Lords committee is to scrutinise the proposals - which are for five pilot schemes at this stage - and to make the Government explain just how they think they will work. To this end I've already tabled more than 30 amendments.

My job is to really put this part of the Bill through the wringer. When we reach it on Wednesday or next Monday that's just what I intend to do!