# The road to MHHS – are your unmetered supplies ready for P434?

- Link: https://imserv.com/blog/the-road-to-mhhs-are-your-unmetered-supplies-ready-for-p434/
- Published: 2024-05-08T09:18:43+00:00

A key stepping stone on the road to MHHS, P434 prepares non-half hourly unmetered

supplies metering systems for the new world of half hourly settlement.

### What is P434?

---

Currently, there are just under 34,000 Unmetered supply MPANs in use across the 
UK –
which are settled via both Non-Half Hourly and Half Hourly routes. The very
nature of anunmetered supply means that all devices, typically street lighting, 
are listed in an inventorythat defines the wattage and method of operation for the
device, and for Non-Half Hourlydevices, grouped into 4 different categories, depending
on how and at what time of the daythe device is used. The customer inventory is 
then split between 1-4 NHH UMS MPANs,dependent on the category. In the new world
of MHHS, there will only need to be one MPANacross the whole portfolio, as profile
class definitions become irrelevant when everything issettled on the half hour.

The Elexon Modification P434, approved by Ofgem in December 2022, is a critical 
step
towards MHHS and needs to be completed before the MHHS milestone M11 in April
2025.

### What do I have to do?

---

Suppliers should have already been working with their Unmetered Supplies Operator
(
UMSO) to determine which of their MPANs should be retained, which should be retired,
andwhich NHH inventories need to be migrated. For larger, more structured portfolios–
thoseowned by larger Local Authorities or Public Sector bodies – this will be relativelystraightforward.
Most of these end user Customers already appoint a Meter Administratordirectly today
and have a HH UMS MPAN already.

For smaller customers, or portfolios that are under 100kW, suppliers will need to
appoint a
Meter Administrator for the first time to conduct the required Change 
of Measurement Class(CoMC) process, and this all needs to be carried out in plenty
of time. Any supplier that hasnot secured an agreement with an Unmetered Meter Administrator
following the 4th of April2024 deadline will now not be able to take on any new 
HH unmetered supplies, with theaccompanying requirement to have a Meter Administrator
appointed.

### What is the CoMC process?

---

The CoMC process involves moving MPANs that are allocated as NHH to a HH
measurement
class. Whilst for metered supplies, this can be quite a time-consumingprocess, for
Unmetered Supplies it is an administrative activity which involves sending therelevant
data flow to change the registration – moving the MPAN from one measurementclass
to another.

However, most customers with unmetered portfolios who have both NHH and HH MPAN’s

could choose to simply move their NHH inventory to their HH MPAN and then retire
the NHHMPAN’s from use.

The complexity arises when a smaller unmetered customer (typically parish councils
or
similar) only has a legacy NHH MPAN for their supply. At that point, suppliers
will need toappoint a Meter Administrator to conduct the CoMC process.

As the industry’s leading Unmetered Supply expert, Power Data Associates, part of
IMSERV,
currently manages over 80% of the UK’s unmetered supply, in the HH arrangements.
Ourindustry experts are collaborating closely with our customers to prepare them
for the newMHHS world and deliver the requirements for P434.

Elexon’s Performance Assurance Board (PAB) has recently written to suppliers to 
ask them
to confirm their plans to deliver on P434, and suppliers need to show how
they are workingclosely with their Meter Administrator to deliver compliance. Talk
to us to see how we canhelp you prepare your unmetered supply portfolio for the 
changes needed to make halfhourly settlement a reality.

Find out more about MHHS – visit our resources here: MHHS for suppliers (white paper).

Find out how we are already helping suppliers with the requirements of P434 in our

latest article [here](https://imserv.com/imserv-backs-major-energy-suppliers-to-go-live-with-p434-an-early-milestone-on-the-road-towards-mhhs/).