PuK - Process Technology & Components 2024

Pumps and Systems
High-efficiency pumps
Significant efficiency gains
Since the EuP Directive came into
force in 2013, virtually the only circulating
pumps installed in Germany
have been high-efficiency pumps.
Nevertheless, there are still millions
of old uncontrolled pumps running
in boiler rooms. These are obviously
worth replacing. A modern highefficiency
pump is around 90 per
cent more efficient than an old, uncontrolled
circulating pump with
the previous energy efficiency class
D rating. For pumps with a typical
size and standard load profile, this
reduces power consumption by approximately
450 kWh per year. With
savings of some 150 euros per year,
even without subsidies the new
pump will have paid for itself within
just a few years.
est Alpha2 today will lead to savings
of more than 100 kWh per year.
Thanks to vast improvements in
efficiency, the flow rates of pumps
have changed so much that an existing
pump can often be replaced
with a smaller type and still provide
the same performance. For example,
an old Magna 40-100 can be replaced
with a Magna3 32-100 or even
a Magna3 25-120, depending on the
operating point. This means that significant
investment cost savings can
be made too. With the right adapter
sets provided for the Magna3 range,
the smaller types can be adapted to
the situation in which they are being
installed. For example, pipe fitting
models can be adapted to an existing
flange connection and the installation
length can be increased from
180 to 220 mm.
Fig. 4: The latest Alpha2 and Alpha3 models
enable a simple hydronic balancing process
that is eligible for a subsidy and saves additional
energy
Fig. 3: If a pump can be replaced with a smaller size to achieve the same flow rate, adapter
sets can be used to adapt the pump to the situation where it is being installed (Grundfos
Magna3)
with the pump and is guided through
the balancing process step by step by
the GO Balance app. This simple procedure
takes less than two hours for
a typical single-family home and is eligible
for a subsidy.
Experience has shown that hydronic
balancing increases the efficiency
of the heating system by 10
to 20 per cent. Despite this, it is estimated
that up to 10 million German
heating systems have not yet been
balanced. This makes it all the more
worthwhile to combine a pump replacement
with hydronic balancing –
yet another reason to get a modern
high-efficiency pump.
A less obvious point is that current
high-efficiency models perform considerably
better even than newer
pumps. This becomes clear when
looking at the best-selling Grundfos
Alpha series, each generation of
which was among the most efficient
in its class at the time. Introduced in
2005, the energy-saving Alpha Pro
model with permanent magnet motor
and integrated frequency converter
was around 62 % more efficient than
the original Alpha released in 2000.
The latest Alpha2 generation is 68 %
more efficient even than the Alpha
Pro, and consumes 88 % less energy
than the 2000 model. Replacing an
energy-saving Alpha Pro with the lat-
Replace and balance
Today’s models, such as Alpha2 or
Magna3, have been hydronically optimised
so much that they are almost
at the limits of what physics will allow.
There are still further developments
taking place, however, mainly
in the area of digital integration. One
example of this is hydronic balancing.
When they leave the factory, both
models are prepared for a process,
developed by Grundfos, in which the
pump provides the necessary data.
The Alpha3 has the necessary wireless
interface already built in, while
the Alpha2 requires the Alpha Reader
tool. The installer pairs a smartphone
The Author: Jochen Krings,
Professional Relations,
Grundfos GmbH, Erkrath, Germany
www.grundfos.de
PROCESS TECHNOLOGY & COMPONENTS 2024
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