Dublin City Council wants to rid the capital's streets of bin bags, meaning a ban could be on the way for thousands of households.
However, it does not know exactly what should be used to replace them - and is offering a €50,000 reward for the solution.
The money can also be divided, among a maximum of three ideas.
A procurement process has been put out to tender by the council.
Legislation requiring the use of wheelie bins instead of bin bags came into force in 2016 - but certain homes and areas were excluded, owing to a lack of space to store the bins.
Dublin City Councillor Mannix Flynn told Newstalk Breakfast this has been a long time coming.
"This has been on the cards for quite some time - some years back, we discussed this whole issue under the Household Waste Storage by-laws.
"We realised then when we were imposing these by-laws about wheelie bins that there wasn't capacity in homes and some apartments to store waste in wheelie bins, and that the black plastic bag was the solution there.
"And we realised that many elderly people weren't able to manoeuvre a wheelie bin in and around their small home".
But he said allowing the continued use of black bin bags "was a temporary solution".
"At the moment if you go out there, the streets are littered with black plastic bags: vermin open them, seagulls open them, the wind - if there's bad adverse weather - there's rubbish thrown all over the street".
But he said they will not impose an unworkable plan.
"We won't see a situation where we're going to impose an unworkable solution on those who are elderly and certainly those who are getting elderly - like yourself and myself".
He also suggested that more frequent rubbish collections could be the answer.
"The issue is that people are going to have to learn how to reduce waste in the home, because many items are thrown into the black plastic bag willy-nilly because you can't see into it.
"So it's about separating waste, making it manageable and perhaps it's even about collecting waste a lot earlier in the week - so there'd be two or three collections of the waste".
