Scottish Learning
Journey to
Heerlen Minewater
District Heating System
2nd-4th March 2016
Attendees & Agenda
Attendees:
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Adam Swainbank – Scottish Development International
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Alex Schlicke – Scene Community
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Amy Bowker - SEPA
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Catherine Cooper – Veitch Cooper
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Craig Murphy – Mitsubishi Electric
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David Pearson – Star Renewables
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David Townsend – Town Rock
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Doreen Reid – Scottish Development International
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Gregor McDonald – Scottish Enterprise
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Jude Maxwell – Scottish Enterprise
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Martin McKay – Clyde Gateway
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Nick Hytiris - Glasgow Caledonian University
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Paul Steen – Ramboll
Agenda:
Day 1 –Workshop:
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Local community and economic perspective by Yvonne Bemelmans, Officer
of Economics
The origin and development of the minewater project 1999-2008, by Elianne
Demollin, NEBER
Reservoir modelling assessing how geothermal minewater systems will react
to predefined exploitation projects by Virginie Harcouet-Menou, VITO
System development of minewater from 1.0 to 3.0, by Rene Verhoeven,
Mijnwater B.V
Energy and geothermal policy development, by Paul Ramsak (RVO NL
agency)
Vision and tour of Maankwartier, by Michiel Huisman
Day 2 – Minewater tour of various important nodes in the system:
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Cluster installation (exchange between cluster grid and mine water grid)
Minewater and heat pump installation at APG Pension Fund (reuse of heat
from datacentre)
Cold and hot injection/extraction wells
Heerlerheide Centrum complex
Discussion on carbon roadmap by Herman Eijdems, Mijnwater B.V
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Introduction to Heerlen Minewater Project
A series of comprehensive reports detailing the development and technical details of
the Heerlen minewater project are available publicly, such as the peer reviewed paper
presented at the 2013 International Renewable Energy Storage Conference1. The
following abstract from this paper provides an overview of the Heerlen minewater
system:
In the last 10 years numerous research and commercial initiatives have been
undertaken in Europe to develop abandoned coal mining fields into low-temperature
resources. One of the most successful is the Minewater project of the municipality of
Heerlen, the Netherlands, where a low-temperature district heating system was
launched in operation in October 2008, under the European Interreg IIIB NWE
programme and the 6th Framework Program project EC-REMINING-lowex. The
Minewater project is now being upgraded from a straight forward pilot system to a fullscale hybrid sustainable energy structure called Minewater 2.0. A totally new concept
which becomes an essential part of the Sustainable Energy Structure Plan of Heerlen
and has the following landmarks:
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Energy exchange instead of energy supply: cluster grids for energy exchange
between buildings and the existing mine water grid for energy exchange
between cluster grids.
Energy storage and regeneration in mine water reservoirs instead of depletion.
Addition of poly-generation: bio-CHP, solar energy, feed in of waste heat (data
centres and industry), cooling towers for peak cold demands.
Enlargement hydraulic and thermal capacity mine water grid through improving
well pumps, pressure boosting systems and reuse of the existing mine water
return pipe for additional supply and disposal of hot mine water.
Fully automatic and demand-driven supply of hot and cold mine water through
usage of pressurized buffer systems at the extraction wells and sophisticated
injections valves at the injection wells.
All geographically dispersed mine water installations at buildings, clusters and
wells are equipped with sophisticated process control units that communicate
with a Central Monitoring System (CMS) through the internet. A very new
application in the build environment.
The first phase of the Minewater 2.0 project is in operation since June 2013.
“Minewater 2.0 Project in Heerlen the Netherlands: Transformation of a Geothermal Mine Water Pilot Project into a Full Scale Hybrid
Sustainable Energy Infrastructure for Heating and Cooling”, 8th International Renewable Energy Storage Conference and Exhibition, IRES,
2013, download available from http://www.sciencedirect.com/science/article/pii/S187661021400174X
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Learning Outcomes/Themes
Several themes emerged throughout the workshop and site tour:The energy landscapes in Scotland/UK and the Netherlands are similar in many
ways:
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In the Netherlands and the UK, coal mining and coal based electricity production
has been largely phased out since the 1960s following the discovery of large
quantities of natural gas in the North Sea. Since then heat has been primarily
delivered domestically and industrially by mains gas in both the Netherlands and
the UK. Coincidentally both countries have almost identical 2020 renewable
targets of 14% and 15% respectively.
Following the closure of coal mines, declines in local economic prosperity with
associated deterioration of the municipal infrastructure has been witnessed, with
Heerlen becoming the poorest town in the Netherlands at one point following the
closure of the coal mining and coal thermal plant. Many former mining towns in
Scotland have seen a similar downtown in economic prosperity following the
collapse of the UK mining industry.
Groundwater rising within the mines is a common issue between Netherlands
and Scotland with the potential impact on the groundwater resource and quality.
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Regaining civic pride through the development and reinvention of the mine in
Heerlen: The development of the minewater system is an inspirational story of the
evolution and reinvention of the town of Heerlen.
 By extracting/storing energy from/in the mine system, the theme of Heerlen
continuing to be a national energy centre continues, and while no longer
producing coal the heritage of the mines continues to this day by providing the
town with energy and a source of pride.
 A repeated theme throughout the visit was the involvement of former
mineworkers as advisors to the project, for example workshops were held and
the miners provided expert knowledge regarding the layout and last known state
of the mines. This also led to a high level of community buy-in to the project and
even a source of civic pride.
 Whilst buy-in and pride are intangible and hard to quantify, local community
involvement in the development and operation of the system would appear to
have played an important part in its inception and operating success – currently
around 29.6 million euro investment and 175,000 m 2 of building space
connected.
Part of the mine water project is the multifunctional complex Heerlerheide Centrum,
where five shops, a conference room, a café, a supermarket and 200 dwellings are
connected to a heating and cooling network
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Heerlen Project Timeline & Funding
Heerlen Project History:
1999
2000 – 2003
2004
2004 – 2008
2008 – 2012
2008 – 2009
2011
2012-2013
November 2013
2014- 2015
First ideas to use mine water as an energy source
Research, lobby and fund raising: Interreg IIIB and EOS
Decision City Council to start Minewater project
Research, design, drilling, construction network.
Funding EC REMINING-lowex and UKR
Realisation and connection first two Minewater energy stations
(HHC: 30.000 m2 & CBS: 22.000 m2)
Decision City Council to establish a Minewater Company
Design & construction Minewater 2.0 system & two new
connections (Arcus 30,000 m2; APG 32,000 m2)
Establishment Minewater Company
175,000 m2 buildings connected; development Minewater 3.0
Heerlen Project Funding & Financing:
European funding:
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Interreg IIIB (€6.4m)
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6th Framework Program project EC REMINING-lowex (€3.5m)
National funding:
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EOS Energy Research Subsidy (€0.3m)
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UKR Unique Opportunity Regulation (€0.6m)
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ISV Investment budget City Renovation (€1.3m)
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Province of Limburg (0,4)
Municipality Heerlen:
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Investment (€2.0m)
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Shares (€5.1m)
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Loan (€10m)
Investment Minewater project end 2015: €29.6m EUR (175,000 m2)
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Heerlen Minewater Project
There are three distinct parts to Heerlen’s Minewater Development.
If Minewater 1.0 had continued operation without change then the modelling predicted
that the thermal resource would have been depleted.
Minewater 1.0 (pilot)
Minewater 2.0
2008 – May 2013
(current) June 2013 – now
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Traditional network (tree)
Only heat and cold supply
Simple change-over-system
Minewater as source
Bivalent energy stations (HP +
Boilers + Chillers)
Mijnwater owner and operator grid
CO2-emission reduction 35%
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Hydraulic cloud network
Instant heat/cold exchange
Minewater as storage
Fully demand driven
Bidirectional wells
Multiple sources
All electric (No gas)
Mijnwater owner/operator network
& energy stations
CO2-emission reduction 65%
Minewater 3.0
(near future)
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Demand
and
supply
side
management (intelligence)
Advanced energy storage (time)
CO2-emission reduction 80 – 100%
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Heerlen Minewater Clusters
In Heerlen they have developed a cluster of buildings approach:
Cluster A - APG pension Fund
building reusing waste heat
from the data centre
Cluster B - Under
construction: Moon Quarter
which is the inspiration of
artist Michiel Huisman – and
comprises a new railway
station, shops and cafes, a
hotel, offices , terraces and
apartments on different floors
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Heerlen District Heating
Specific details relating to the Heerlen low temperature district heating
operation:
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The Heerlen system runs without a conventional central plant (e.g. without a
large-scale CHP or similar), and instead uses decentralised energy stations at
the end-users and a variety of inputs including excess heat from industry in
addition to the minewater geothermal source.
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The minewater reservoir is used as a (seasonal) storage.
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The system has a minewater backbone, 3 pipe system (hot, cold and back-up
pipe) with two production and two injection wells (hot and cold) and one
collective return injection well for back-up if required. In 2016 all hot and cold
wells will be bidirectional suited for production and injection of mine water.
Network pipes are plastic or stainless steel 316.
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The temperatures are much lower than “standard” UK
district heating schemes designed to operate at
65-80C (for compatibility with conventional wet
radiator systems). Typically the Heerlen system runs
with a temperature difference of around 12C
(25-28C and 16-18C for the hot and cold return
respectively). All buildings require local heat pumps to
raise the temperature to 40C for heating, and
individual booster heat pumps to raise the
temperature further, up to 65C for domestic hot
water. At Heerlen they have developed energy
stations that can use the available heat and cold from
the grid as passively as possible. So if higher
temperatures are available due to heat sources with
higher temperatures, e.g. industrial waste heat or
summer solar, then this heat can be used passively,
or with reduced use of the heat pumps, depending on
the required return temperature to the grid at that
time.
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The minewater system architecture makes planning for future expansion
economically viable; the distribution pipes can be oversized during the build to
enable future expansion and also lower temperatures result in lower system
losses. By avoiding a central plant there are no economic concerns about a
central plant running at low utilisation during the early phases of the project and
there is no need to upgrade the thermal plant in order to expand the system.
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There is potential for smart operation, such as staggering demand to enable
peak shaving and valley filling alongside thermal buffering through distributed
sub-surface thermal buffers. Examples include heating office clusters between
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5am-7am, then making heat available for domestic clusters to meet the hot water
load between 7am-9am.
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If higher temperature waste heat is injected to the minewater reservoir, then the
temperature will dissipate over time (the heat is not lost but will degrade to lower
temperatures due to heating up colder mine water and rocks), therefore smart
control is required to ensure it is primary utilised instantly and passively by
exchange (between buildings in cluster grids and between cluster grids through
the mine water grid). The cluster grids are designed for a maximum temperature
of 50 degrees. Higher temperatures are possible but demands additional
measures for coping with mechanical forces due to (thermal) expansion of the
network. In this system higher temperatures are simply not required because of
the low-temperature approach (low quality local sources for low quality
applications like heating of buildings).
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The Heerlen system is comprised of a series of containerised concrete cluster
energy centres, each about 25 to 30 tonnes which are installed underground,
and are accessible by surface hatches. This approach allows offsite construction
and rapid installation, leading to a very low visual impact system which is robust
to vandalism.
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The current 2.0 system can be remotely monitored and controlled
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The Coefficient of Performance of the entire system is of the order of 25.
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In the mine water grid plastic pipes or stainless steel 316 up to 12 bar system
pressure are used to avoid the risk of corrosion by the mine water.
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The cluster grids are closed grids which are hydraulically separated from the
mine water grid. Simple steel pipes are used. The system is filled with
demineralised water and water quality is maintained by a simple water treatment
system.
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Minewater 3.0 = balancing of demand and supply. It includes the opportunity to
bypass heating or cooling heat pumps in the buildings and also intelligent top
level control above process control level. Controlling total system decisions and
understanding forecast building energy demand – prediction of demand and fill
demand in an optimal manner along with spread demand and generation. Also
market interaction by optimising costs and revenues through buffer storage.
Exergy - extracting the maximum useful work from a unit of energy (and hence
reducing emissions): Repeated throughout the 2 days of discussions was the theme of exergy: the use
high quality sources (e.g. gas or biomass) for high quality applications (transport,
industry, electricity) and low quality sources (e.g. low temperature waste heat,
ground water/ mine water) for low quality applications like heating and cooling of
buildings. It is the concept of extracting the maximum utility out of a unit of
energy by using heat appropriately. This can be understood as the idea that
using high value commodities such as gas to provide low grade heating is
intuitively wasteful of a valuable resource. More value and more energy, and
therefore overall reduced emissions, can be extracted from using high value
sources more exclusively, and then reusing the lower grade output heat for
space heating applications. For example, a standard gas boiler runs at an
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exergetic efficiency of about 18%, a heat pump 45% and the thermal smart grid
(a 3.0 system) could run at over 90%.
Compared to the previous heating systems the Heerlen minewater system
replaced, the 1.0 system realised a 35% CO2 reduction and the 2.0 system a
65% CO2 reduction.
Modelling and feasibility phase:VITO modelling allows thermal hydraulic dynamic simulation modelling of the
hydrogeology impact of heat production and reinjection and consideration of potential
for storage. Vito presented an overview of the feasibility and modelling phase of the
project which involved a full evaluation of the resource including studies of the:
 Geometry and structure of the subsurface works
 Local geology
o Understanding relationships between multiple mine concessions and
mining history and abandonment process.
o Elevation model – mine maps, mine state (open/closed), connections
between concessions, well and shaft locations.
 Hydrology and water quality
o Flow at local and regional scale, influence of faulting, flooding history,
water quality and source
 Thermal data
o Geothermal gradient, rock thermal properties, temperature measurements
during/after mining.
Heerlen has a very dynamic water table which has been rising since the 1980’s and this
has been included in the modelling.
Miscellaneous points:
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Importantly in terms of supporting geothermal heat in the Netherlands, the Dutch
government offers up to 85% warranty on the cost of a borehole drill as an
incentive to overcome the risk faced by individual stakeholders (e.g. a tomato
farmer).
A new mining act was introduced in 2003 which changed liability with onus of
proof now residing with the plaintiff. Heerlen was the first applicant under the
newly introduced law.
Developing a communication strategy was an integral part of the project from the
outset with a clear communication strategy developed for each phase of the
project. Early press releases helped to secure local pride and involvement which
also helped to drive positive political support.
A very tight technical brief is required – for Heerlen 1.0 the tender companies
took advantage of weak areas of the brief which led to increased project costs.
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