Residual rubbish refers to that which cannot be economically re-used, recycled or composted.
A Waste Flow Model has been created by Project Transform to look at how much rubbish people are likely to produce and how much of this can be recycled.
When the model was first run in 2007, it indicated that 305,000 tonnes of residual waste would be produced by 2042 however the latest figures indicate this is now likely to be 284,000 tonnes.
The model also forecasts that by 2042 the overall household recycling rate across the three areas will be an estimated 54%.
The complex model considered how many tonnes of waste are currently recycled and composted and how much waste might be created in future as society changes.
Project Transform is a partnership between Coventry City Council, Solihull Metropolitan Borough Council and Warwickshire County Council which aims to reduce the amount of waste produced within the sub-region as well as increasing the amount of waste which is recycled or composted.
Talking about the new figures Solihull councillor Kate Wild said: This is a really sophisticated model which is helping us to understand how the picture of waste and recycling may change over a long period of time.