Fuel poverty is guaranteed to rise as we know that prices will go up. Unless the government privatises the fuel companies or caps the profits that can be given to shareholders, that is a given; and inflation, higher mortgage rates, rent increases and the cost of food will make things worse.
What I don't understand is how those figures have been arrived at with such specificity. Why do couples with 3 or more children earn less or spend more on fuel? I understand that there will be more washing of clothes and children than for couples with smaller families, but surely everything else will even out? 85% seems high, when many of them will have two salaries and be at work all day. Someone with one baby who is on maternity leave and needs the heating on to keep the baby warm is going to use more than parents of school-age children, surely, and be more likely to be on a reduced salary.
If the figures take into account other spending (eg buying food, clothes, toys etc for larger families) then we aren't really talking about food poverty, but about poverty in general. Yes, the cost of fuel exacerbates it, but figures like this have to stand up to scrutiny, and if I can see holes in them so will everyone else. I struggle to believe that Gordon Brown would be so slapdash - in what context were they produced?