Open call for evidence

Reviewing double reward classification of unrefined liquid dextrose ultrafiltration retentate (ULDUR)

Published 13 March 2025

Introduction

Unrefined liquid dextrose ultrafiltration retentate (ULDUR) is currently eligible for double reward under the Renewable Transport Fuel Obligation (RTFO) as a processing residue, providing it meets the description in the department’s list of feedstocks.

We are publishing this call for evidence in response to concerns which have been raised about whether there are other viable end uses for ULDUR and whether volumes of this feedstock being produced are at the level we would expect relative to the intended end product.

While the department wishes to encourage the supply of waste feedstocks under the RTFO, we need to be satisfied that these materials meet the required criteria for such support. This includes reviewing the eligibility for double reward as and when appropriate.

Initial assessment

ULDUR was assessed and subsequently approved as an RTFO feedstock in October 2022.

Reviewing the categorisation of materials

As set out in the RTFO and SAF Mandate technical guidance, the administrator may periodically review and update the list of feedstocks to add new materials or change the listing of existing ones if sufficient evidence emerges to indicate that they should be treated differently.

Reported volume of bioethanol derived from ULDUR under the RTFO

Image 1: volume of bioethanol derived from ULDUR, under RTFO

Table 1: volume of bioethanol derived from ULDUR, under RTFO

Feedstock 2022 in million litres 2023 in million litres 2024 in million litres (provisional)
Corn 606.4 466.8 464.6
Sugar cane 236.7 219.7 56.9
Wheat 152.8 204.3 87.4
Starch slurry (waste) 92.9 130.7 102.0
ULDUR 0.0 269.6 339.1
Other 150.6 114.5 110.1

Call for evidence themes

Other end uses of ULDUR

The double reward status of a feedstock is primarily determined by whether or not there are other economically viable alternative end uses for a material. This is the matter that we are asking for evidence on.

Questions

Are you aware of any instances where ULDUR could be considered as having any economically viable end uses other than ethanol production?

Are you aware of any standard industry practices, not including ethanol production, for the management and treatment of the ULDUR waste stream?

Feedstock description

The administrator would like to re-examine the agreed definition of the feedstock. The ULDUR definition is:

a processing residue generated during the corn wet mill sweetener refining process. Dry matter must not exceed 40% and particles must be retained by filtration system having pore size between 0.001 and 0.1micron or with a molecular weight cut off between 1,000 and 500,000 dalton.

Questions

Do you agree or disagree that the current description of ULDUR is sufficient to support only double counting material?

If amended, what, in your view, would be a reasonable notice period between announcing and implementing any changes to the feedstock description of ULDUR or classification of ULDUR as a double counting process residue and why (providing evidence where possible)?

Specification

The feedstock is currently determined as a ‘processing residue’ which is defined in the RTFO Order 2007 as:

a substance that is not the end product sought directly from the process, the production of which is not a primary aim of the process and in respect of which the process has not been deliberately modified in order to produce it.

Questions

What, if any, information and evidence do you have with relation to the amounts of ULDUR generated relative to the intended end product?

What, if any, other information and evidence would you like us to consider regarding ULDUR?

How to respond

See the Ways to respond section of the call for evidence page on GOV.UK to find out how you can respond to this call for evidence.

The call for evidence began on  13 March 2025 and will run until 11:59pm on 5 June 2025. Ensure your response reaches us before the closing date.

Full list of questions

Are you aware of any instances where ULDUR could be considered as having any economically viable end uses other than ethanol production?

Are you aware of any standard industry practices, not including ethanol production, for the management and treatment of the ULDUR waste stream?

Do you agree or disagree that the current description of ULDUR is sufficient to support only double counting material?

If amended, what, in your view, would be a reasonable notice period between announcing and implementing any changes to the feedstock description of ULDUR or classification of ULDUR as a double counting process residue and why (providing evidence where possible)?

What, if any, information and evidence do you have with relation to the amounts of ULDUR generated relative to the intended end product?

What, if any, other information and evidence would you like us to consider regarding ULDUR?

Freedom of Information

Information provided in response to this call for evidence, including personal information, may be subject to publication or disclosure in accordance with the Freedom of Information Act 2000 (FOIA) or the Environmental Information Regulations 2004. 

If you want information that you provide to be treated as confidential, please be aware that, under the FOIA, there is a statutory code of practice with which public authorities must comply and which deals, amongst other things, with obligations of confidence. 

In view of this, it would be helpful if you could explain to us why you regard the information you have provided as confidential. If we receive a request for disclosure of the information, we will take full account of your explanation, but we cannot give an assurance that confidentiality can be maintained in all circumstances. An automatic confidentiality disclaimer generated by your IT system will not, of itself, be regarded as binding on the Department for Transport. 

DfT will process your personal data in accordance with the Data Protection Act (DPA) and in the majority of circumstances this will mean that your personal data will not be disclosed to third parties.

Confidentiality and data protection

View our DfT online form and survey privacy notice for more information on how your personal data is processed in relation to this survey.

Do not include personal information in your responses unless specifically requested.