Introduction to geothermal energy Freek van der Meer Presented at Dar Es Salaam Institute of Technology, DIT, Wednesday 26 October 2016

Why invest in renewable energy? What is geothermal energy? Where are geothermal resources available? Power generation from geothermal; technology Geothermal project development

2

3

INTRODUCTION TO THE UNIVERSITY OF TWENTE

4

UNIVERSITY OF TWENTE

• An entrepreneurial campus university established in 1961 • More than 10,000 students • 3,300 staff members

HIGH TECH HUMAN TOUCH • Societal impact: making a real difference • Synergy: excellence in combinations • Entrepreneurship and innovation • Internationalization: tomorrow’s global citizens.

UT IN ONE SLIDE

Five faculties BMS Behavioural, Management and Social sciences CTW Engineering Technology EWI Electrical Engineering, Mathematics and Computer Science TNW Science and Technology ITC Geo-Information Science and Earth Observation

Four research institutes CTIT Centre for Telematics and Information Technology IGS Institute for Innovation and Governance Studies MESA+ Institute for Nanotechnology MIRA Institute for Biomedical Technology and Technical Medicine

Virtual institutes Twente Graduate School (MSc+PhD) ATLAS “university college”

ITC FACULTY OF GEO-INFORMATION SCIENCE AND EARTH OBSERVATION

About ITC Established: 1950 - Appeal by UN in framework of official development

assistance - ODA Aim: Build capacity for economic development in developing world Main instrument: Postgraduate education and training, research, project

services Main field of science: earth observation, geoinformation science applied to

problem-solving in earth sciences, natural and water resources and urban studies

Achievements 23 000 alumni (predominantly) mid-career professionals

ITC ALUMNI

29/10/2016 To modi

Why invest in renewable energy? What is geothermal energy? Where are geothermal resources available? Power generation from geothermal; technology Geothermal project development

OVERVIEW OF THE PRESENTATION

10

GLOBAL LAND/SEA TEMPERATURE INCREASES

11

ipcc

Source: NASA

IS OUR CLIMATE CHANGING: YES

12

BUT OUR CLIMATE ALWAYS HAS CHANGED - TRUE

13

Present day

CO2 IS KEY BUT LINK WITH TEMPERATURE IS LOST

14

IS OUR CLIMATE CHANGING?

15

CO2 EMISSION – THE BIG PROBLEM

16

Energy transition debate

17

We set a new record on CO2 release!!! Carbon release rates from anthropogenic sources reached a record in 2014! Geologic analogues from past transient climate changes show that this high exceeds the Palaeocene–Eocene Thermal Maximum known at present to have the highest carbon release rates of the past 66 million years.

18

GLOBAL NETWORK OF TIDE GAUGES (2001)

INCREASE OF SEA-LEVEL HEIGHT THROUGHOUT

20th CENTURY

1,5 to 2 mm/year

Secondary effects of climate change

Number of events, impacts, extreme events are increasing

Driving forces: Climate change Vulnerability changes: population growth urbanization (coastal zones, floodplains) occupation of marginal lands

(Better recording of disastrous events?)

Source: WWW.EM-DAT.NET, 2007

1. frequency at which natural disasters occur is increasing 2. more extreme events occur 3. this applies to hydrometeorological hazards

20

• Transition from fossil fuels to renewable energy sources is one of the biggest challenges and game changers for the coming decades but an essential one if we wish to reach the agreements of COP21 (Paris Agreement) in view of combatting climate change and global warming.

• In COP21, for the first time in over 20 years of UN negotiations, countries ratified an agreement ‘to achieve a legally binding and universal agreement on climate, with the aim of keeping global warming below 2°C.’

ENERGY TRANSITION FROM FOSSIL FUELS TO RENEWABLES

21

Why invest in renewable energy? What is geothermal energy? Where are geothermal resources available? Power generation from geothermal; technology Geothermal project development

OVERVIEW OF THE PRESENTATION

22

October 29, 2016 23

What is geothermal?

“Geothermal derives from the Greek and means "Earth heat" - which geologists understand as describing hot rocks, volcanic activity or heat derived from deep within the earth” - wikipedia.

Sources of Earth’s Internal Energy

•70% comes from the decay of radioactive nuclei with long half lives that are embedded within the Earth

•Some energy is from residual heat left over from Earths formation.

•The rest of the energy comes from meteorite impacts.

PLATE TECTONICS

25

GEOLOGY AND GEOTHERMAL POTENTIAL SUBDUCTION ZONE VOLCANISM->INDONESIA, PHILIPPINES

26

GEOLOGY AND GEOTHERMAL ENERGY MID OCEANIC RIDGE->ICELAND

27

GEOLOGY AND GEOTHERMAL ENERGY EAST AFRICAN RIFT SYSTEM

28

Why invest in renewable energy? What is geothermal energy? Where are geothermal resources available? Power generation from geothermal; technology Geothermal project development

OVERVIEW OF THE PRESENTATION

29

Availability of Geothermal Energy

On average, the Earth emits 1/16 W/m2. However, this number can be much higher in areas such as regions near volcanoes, hot springs and fumaroles.

As a rough rule, 1 km3 of hot rock cooled by 1000C will yield 30 MW of electricity over thirty years.

There is believed to be enough heat radiating from the center of the Earth to fulfill human energy demands for the remainder of the biosphere’s lifetime.

Volcanic geothermal systems are in one way or another associated with volcanic activity.

Convective fracture controlled systems the heat source is the hot crust at depth where geothermal water circulated to considerable depth (> 1 km), mostly through vertical fractures

Sedimentary geothermal systems are found areas with permeable sedimentary layers at great depths (> 1 km) and above average geothermal gradients (> 30º C/km).

Geo-pressured systems fluid caught in stratigraphic traps may have pressures close to lithostatic values.

Hot dry rock (HDR) or enhanced (engineered) geothermal systems (EGS) consist of volumes of rock that have been heated by volcanism or abnormally high heat flow.

TYPE OF GEOTHERMAL SYSTEMS GEOLOGICALLY

31

32

October 29, 2016 33

Use

INSTALLED GEOTHERMAL CAPACITY

Why invest in renewable energy? What is geothermal energy? Where are geothermal resources available? Power generation from geothermal; technology Geothermal project development

OVERVIEW OF THE PRESENTATION

36

37 Source: ESMAP geothermal handbook

How Direct Use Works

•Direct Sources function by sending water down a well to be heated by the Earth’s warmth.

•Then a heat pump is used to take the heat from the underground water to the substance that heats the house.

• Then after the water it is cooled is injected back into the Earth.

Direct uses of geothermal energy is appropriate for sources below 1500C • space heating • air conditioning • industrial processes • drying • Greenhouses • Aguaculture • hot water • resorts and pools • melting snow

October 29, 2016 40

Netherlands Direct use: Process heat in industries

Heineken, FrieslandCampina, Pulp&paper factories

Medium enthalpy electricity: Texel, Hoogeveen, Apeldoorn, Schiphol Airport

2008

‘Warmte-koude opslag’

‘heating and cooling’

Low enthalpy=low value: risk MUST be low!; success rate MUST be high! Create a full 3D model of the subsurface Only GO when 90 % chance of success

NK YOU

Ground Heat Collectors

This system uses horizontal loops filled with circulating water at a depth of 80 to 160 cm underground.

This type uses one or two underground vertical loops that extend 150 meters below the surface.

Generation of Electricity is appropriate for sources >150oC

Dry Steam Plants: These were the first type of plants created. They use underground steam to directly turn the turbines.

Binary Cycle Plants: This system passes moderately hot geothermal water past a liquid, usually an organic fluid, that has a lower boiling point. The resulting steam from the organic liquid drives the turbines. This process does not produce any emissions and the water temperature needed for the water is lower than that needed in the Flash Steam Plants (2500F – 3600F).

Casa Diablo

October 29, 2016 46

Pros and Cons – geothermal energy

+Geothermal plants can be online 100%-90% of the time. Coal plants can only be online 75% of the time and nuclear plants can only be online 65% of the time. ++Geothermal electric plants production in 13 g/kWh of Carbon dioxide, the CO2 emissions are 453 g/kWh for natural gas, 906g g/kWh for oil and 1042 g/kWh for coal. --Earthquakes, Heat depletion, Natural cooling of Earth’s crust cannot be avoided ---Building costs: $1175-1750 per kW installed capacity --Geothermal areas aren’t always near electricity grids ----High exploration risk

Energy Source Categories

080101

Non renewable

Renewable

Conventional Coal Oil

Gas Nuclear Fission

Wood Hydro

Human/Animal Wind Water Pumping

Alternative Geothermal Oil Shale Tar Sands Methane Hydrates

Wind Solar Biomass/Geothermal?

Wave/Tide Ocean Current

Sustainable means using less than is renewed; if water is withdrawn from a dam faster than it is refilled, the level drops and hydro power is lessened, and finally fails

Why invest in renewable energy? What is geothermal energy? Where are geothermal resources available? Power generation from geothermal; technology Geothermal project development

OVERVIEW OF THE PRESENTATION

49

50 Source: ESMAP geothermal handbook

51 Source: ESMAP geothermal handbook

52 Source: ESMAP geothermal handbook

53 Source: ESMAP geothermal handbook

54 Source: ESMAP geothermal handbook

55

ENSCHEDE THE NETHERLANDS WWW.ITC.NL