Geothermal Energy in New Zealand

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Group 10 Name Student ID Lorena Gallardo 613776 Yuxiang Ma 630337 Harry Smithers 391880 Andre Costa 647254 Tengku Azrai Redza 368816 Image on cover is Wairakei Power Station. Sourced from google.com

24TH October 2013 Word Count: 9019 words

Energy Efficiency Technology ENEN90011 Final Report

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ABSTRACT

This report investigates the barriers and opportunities to exploiting geothermal energy in New

Zealand as a renewable energy source for producing electricity. The report includes relevant

background information regarding geothermal energy as well as summarized technical

information about geothermal energy generation.

The report applies the Triple Bottom Line (TBL) method of considering the social,

environmental and economic aspects of geothermal energy in order to evaluate its

sustainability and viability for further development. It is shown that from an economic

perspective, geothermal energys capital costs are mostly related to the high risk it represents

and the long periods of time taken to obtain revenues. However, geothermal electricity has

low operational costs and therefore, it is cheap to use, it is also reliable, provides funds for

taxes and generates employment. From a social point of view, geothermal energy represents

an opportunity to enhance equity in the New Zealand population. The revenues obtained from

this activity can provide benefits to local and indigenous communities such as the Maori.

Also, as New Zealand is a world leader in geothermal energy, this acquired knowledge is a

form of human capital that brings positive outcomes to the society. Finally, from an

environmental perspective, geothermal energy has low or almost zero carbon emissions

compared to fossil fuel energy sources which contributes to the reduction of greenhouse

gases emissions and therefore, to minimizing climate change. Nevertheless, geothermal

energy plants can cause environmental impacts such as water pollution and subsidence in

land. Therefore, it is necessary to use the available and appropriate technology to avoid these

impacts. At the end of the report, recommendations and conclusions are presented which are

essential to take into account to understand the importance of geothermal energy in producing

electricity in New Zealand.


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Table of Contents

ABSTRACT ................................................................................................................................................ 0

1. AIM .................................................................................................................................................. 3

2. INTRODUCTION ............................................................................................................................... 3

3. TECHNICAL ASPECTS AND APPLICATION......................................................................................... 4

4. COMPONENTS FOR ANALYSIS ......................................................................................................... 7

4.1 Economics of Geothermal Energy ................................................................................................. 7

Financial Barriers ............................................................................................................................. 7

Risk Evaluation ................................................................................................................................ 9

Risk Mitigation .............................................................................................................................. 11

Financial Benefits .......................................................................................................................... 12

4.2 Environmental Impacts ............................................................................................................... 14

Geothermal Energy Generation Impacts ...................................................................................... 14

Environmental Impact of Different Suppliers of Electricity in New Zealand ................................ 17

4.3 Social Barriers and Opportunities ......................................................................................... 20

The opportunity to lead the world The potential for New Zealand to become a world leader in

Geothermal ................................................................................................................................... 20

Geothermal: Delivering benefits locally........................................................................................ 22

Impacts on Culturally Significant Sites .......................................................................................... 24

5. RECOMMENDATIONS.................................................................................................................... 25

6. CONCLUSION ................................................................................................................................. 26

REFERENCES .......................................................................................................................................... 27


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1. AIM

The aim of the report is to identify all barriers and opportunities in regards to operation of

geothermal plants used to utilize the aforementioned source of renewable energy into

meeting New Zealands populations electricity demand. Taken into consideration are the

externalities, production efficiency and quantity of the energy source, specifically in the

chosen country. With the results from the analysis, it is hoped that this report will

determine the feasibility of geothermal energy in New Zealand, and whether or not

further growth for the renewable source is to be encouraged.

2. INTRODUCTION

With the rise in anthropogenic climate change and increasing greenhouse gas (GHG)

emissions, it is becoming essential to shift the reliance of producing electricity via fossil

fuel to renewable energy sources. Currently, 74 percent of electricity used in New

Zealand is generated from renewable sources. 11 percent of it originates from geothermal

energy.

This report involves a sustainability analysis of geothermal energy in New Zealand by

applying the Triple Bottom Line method. The 3 main components of economic effects,

social impacts and environment effects applicable to geothermal energy are extensively

discussed. The perspectives and roles of all parties both directly and indirectly affected by

geothermal energy usage and development are included in the discussion build up.

Comparisons are drawn between other energy sources, namely fossil fuels, wind turbines

and hydropower.

A description of the technical aspects and application of geothermal energy is presented

to provide sufficient background information to assist with the feasibility analysis as well

as introducing the technology. Finally, a conclusion for geothermal energys future in

New Zealand is drawn from the TBL investigation which also encompasses

recommendations for efforts to further develop the energy source if it is considered to be

a viable source of energy to the country.


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3. TECHNICAL ASPECTS AND APPLICATION As well as some historical context, this report also aims to provide information on the

technical functioning of geothermal energy and more specifically, electricity. This

information is required to assess the technical benefits and problems caused by geothermal

energy, thus aids in reaching the reports aim.

The Earth generates and stores important amounts of thermal energy which is commonly

known as geothermal energy. This natural heat is located in the different layers of Earth:

core, mantle and crust. Some studies show that the temperature of the crust and the centre of

the Earth vary, having up to 1000 C in the former and up to 4500 C in the latter

(Fridleifsson and Freeston, 1994b). Geothermal energy has consistently been known as a

renewable energy resource since the centre of the Earth has a stable heat flow. This statement

is correct when the extraction rates are considered which means that there is a net balance

between what it is extracted and replenished. In a human time scale this may not be the case

(Fridleifsson and Freeston, 1994b).

Geothermal resources are usually located in the areas of the Earths crust where higher heat

flux cause the heating of existing water in reservoirs at depth (Barbier, 2002). These

reservoirs are mainly formed by permeable rocks that let water to flow through and permit

heat exchange from rock formations with higher temperatures to reservoirs at reachable

depths for successful extraction. Also, the surface formation cold water needs to be separated

in a natural form from the fluid in the reservoirs (Fridleifsson and Freeston, 1994b).

Permeability should allow or prevent fluid movement by varying approximately four orders

of magnitude within sedimentary basins. However, in order to define an entire geothermal

reservoir it is not enough to know the temperature field in an area (Huenges and Ledru,

2010).

Conduction is the mechanism that allows heat move from the interior towards the exterior.

This mechanism makes the temperature rise as the depth increases in the crust, reaching

temperatures of 25 to 30 C/km on average (Fridleifsson and Freeston, 1994b). The thermal

properties of the rocks as well as thermal boundary conditions control the temperatures that

can be found in the crust. As mentioned above, it is possible to get a probable geotherm in

average if there is enough information of the mantle heat flow and heat production in the

crust. However, as the crustal composition is so heterogenic, it causes local variations

obtaining extremely high temperatures at a few kilometres depth (Huenges and Ledru, 2010).

Nevertheless, the depths where most of the earths heat is stored are too big and therefore,

hard to be reached by humans (Fridleifsson and Freeston, 1994b).

Utilization of geothermal energy is usually divided into two types: direct (i.e. thermal) and

indirect (i.e. electric production). Direct utilization has many advantages compared to

electricity production from geothermal energy. One important benefit is that it achieves

higher conversion efficiency values that vary around 50 to 70% as opposed to 5 to 20% for

traditional geothermal electric plants. Also, direct applications development generally takes


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shorter periods of time, and usually a lower initial capital investment is involved. Moreover,

direct geothermal energy uses not only the high temperature resources but can also use the

lower ones; hence, it is easier to apply around the world (Fridleifsson and Freeston, 1994b).

Electricity generated from geothermal energy can be obtained by direct intake or condensing

plants. The least expensive and simplest form is the direct-intake non-condensing cycle.

Geothermal well steam is passed through a turbine and released to the exterior: the turbine

outlet does not count with any condenser (Barbier, 2002). The reason is because these cycles

use around 15 to 25 kg of steam per kWh generated. If the amount of non-condensable gases

in the steam is very high (more than 50% in weight) then it is recommendable to use these

systems. Also, due to the high energy demand to remove the gases from the condenser, the

non-condensing cycle is preferred when the gas content exceeds 15% (Barbier, 2002). On the

other hand, when the gas content of the steam is lower than 15%, then the condensing plants

are more adequate. They have condensers at the outlet of the turbine and the cooling towers

consume less steam with values that fluctuate around 6 to 10 kg of steam per kWh generated

(Barbier, 2002).

Figure 1: Simplified diagram of a geothermal power plant (British Geological Survey

2013).


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In order to produce power from geothermal energy, it is necessary to be capable of

transforming the direct buried energy (geothermal heat) to electrical power. This can be

accomplished by exchanging the heat from the inner parts of the Earth to a surface and

creating facilities that can efficiently turn one type of energy into another (Glassley, 2010).

To do so, it is essential to have the appropriate equipment which comprises a piping complex

that is able to take the high temperature liquids from depth to a turbine facility on the surface.

Here, thermal energy is used to rotate a turbine and thus, it is transformed to kinetic energy.

The next step is to transform the obtained kinetic energy into electrical energy and this can be

done by using an electrical generator. A simple equation shows the amount of electrical

energy that can be obtained from the earth fluid:

Where is the produced power given in watts (Joules/second), is the efficiency of

the electrical generator, is the efficiency of the turbine, and Hg is the speed at which

thermal energy is delivered to the turbine (Glassley, 2010).


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4. COMPONENTS FOR ANALYSIS The components mentioned previously are discussed in the following sections.

4.1 Economics of Geothermal Energy Applying the economy component of the Triple bottom Line sustainability measurement

allows a substantial evaluation of the financial aspects related to implementing and operating

geothermal energy plants in New Zealand. The discussion method involves highlighting both

financial barriers and benefits of the renewable energy technology. The partys considered to

have direct relation includes New Zealand government, renewable energy investors,

operating companies and energy consumers.

Financial Barriers

Factors contributing to hamper the progress of geothermal energy come from multiple

sources both globally and locally within New Zealand. Identifying these sources will allow a

thorough understanding of the reasons behind the technologys stunted growth and will assist

in producing an answer to whether geothermal energys development is to be pursued.

On a local scale, the role of the New Zealand government and its stand on the technology is

analysed. The government (enforced by Ministry for the Environment) first introduced the

New Zealand Emission Trading Scheme (NZ ETS) in 2008. The plan serves the purpose of

representing New Zealands primary response to global climate change (Ministry for the

Environment 2013). NZ ETS operates by putting value on greenhouse gases (GHG) to

provide an incentive for industries to reduce GHG emissions. However, as stated by Ministry

for the Environment (2013), geothermal energy is considered as stationary energy sector and

is obligated to surrender New Zealand Units (NZU: value of GHG emissions) to the

government and does not receive any allocation of NZUs. This is mainly due to the fact that

products derived from geothermal energy such as power and heat are not entitled to a

premium that can be levied nor enable production of niche products (EGEC 2013).

Furthermore, NZUs are priced at $25 per NZU which contributes to the cost of operating a

geothermal plant (Ministry of Environment 2013).

The global economy is a major factor towards geothermal energys progress as it

significantly influences the financing of the technology. Salmon et al. (2011) has pointed out

that the global credit crunch and economic contraction which started in 2008 had adverse

effects on the renewable energy financing field. The amount of loan losses and bankruptcies

increased which in turn caused many financial providers to be more risk averse, as

geothermal energy is a high-risk venture it was particularly susceptible. This will be

discussed later in this section. Limited financing for geothermal energy in New Zealand has

caused reduced funding of research and development as well as construction of new

geothermal plants in New Zealand in the same period (NZGA 2010). The government shifted


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its priority of developing renewable energy sources to hydro power and wind turbines due to

its higher potential output in the country. However, after managing to identify electricity

demand shortages due to dry years which heavily impacted hydro power output in 2010,

the government has once again reconciled with the plan to develop geothermal energy to

become a more prominent renewable energy source and encourages more financial

institutions to invest (NZGA 2010).

New Zealand utilizes an array of renewable energy source to meet the countrys electricity

demand. Therefore it is understandable to draw comparisons between geothermal to hydro

power and wind turbines as the other main energy source used by New Zealand. Capital cost

on average for all three energy source are as follows:

a) Geothermal energy = $3500/kW - $5000/kW (NZGA 2010)

b) Wind Turbines = $1700/kW $2150/kW (IRENA 2012)

c) Hydropower = $1000/kW $2550/kW (Oils, D 2013)

It is apparent that geothermal energy has the highest capital cost of all renewable energy

sources on average. However, other factors must be taken into account such as reliability of

energy output. Wind turbines and hydropower for example does not have the consistency in

generating power as compared to geothermal energy as they are both affected by

environmental factors such as low wind conditions and dry season respectively (East Harbour

Energy LTD. 2011).

The most prominent reason of requiring financial investors for geothermal energy is its high

capital cost. Geothermal energy sources have potential to generate output ranging between

3.5 and 5 million dollars of capital cost per MWe (NZGA 2010). The high capital cost is due

to the 3 earliest and highest risk development phases (exploration phases) which consists of

resource identification, resource evaluation and test-well drilling (Salmon et al. 2011). These

are the project phases that differ geothermal from oil and gas exploration. Obtaining

financing for these phases is difficult because it does not guarantee returns to the investors.

Furthermore, upfront capital investments also include installation of plant and equipment

(Hughes G & Diogo W, 2004). Hughes and Diogo (2004) states that geothermal projects

usually require a lengthy period of time before generating revenue which usually cause

investors considerable concern with any risks of project delay. Many large (50MWe or

larger) geothermal projects takes up to 10 years before it is fully developed (Harvey C 2013).

High capital cost is mainly due to geothermal projects being a high-risk investment. Harvey

(2013) states that many of the risks are identical to those faced for any grid-connected power

project but there are additional factors specifically associated to geothermal projects which

further impacts on willingness of investors to fund them. The following section will discuss

geothermal related risks as the main contributor to capital cost.


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Risk Evaluation

Geothermal energy is low-emission, scalable and cost competitive. Its potential for new

investment opportunities is very appealing to the current industry. The investors and

governments all provide the fundamental infrastructure and services to develop and deploy

geothermal technologies. However, the increasing investment in geothermal energy also

brings demands for the highest standards of engineering design, construction and

management. Therefore, evaluating the risks of the project is necessary.

Based on the research, there are two primary types of investors for geothermal energy

projects. One is large traditional energy service companies that have the financial ability to

support their investment. While another one is some small developers who are seeking

investment for project funding. Although, these two types of investors evaluate risks

differently, they both require the access to the infrastructure and returns on the

capitals.(Deloitte, 2008)

In order to do this, there are several fundamental risks that they must analyse. Firstly,

geothermal projects often contain high risks in design and construction phase. For example,

there is a high possibility of drilling a dry hole causing the transmission system built for the

geothermal resources not to be put to use. These risks all can change the project schedule

significantly. Secondly, the regulations made by governments can have a serious impact on

the investment. For example, most of the geothermal resources are located in remote areas,

which are owned by the federal government. The land leasing procedure for developing such

projects can be difficult especially when conflicting with other land use. Lastly, there are also

market risks associated with procurement. For instance, the cost for drilling and materials

used in power plants fluctuates all the time due to changes in exchange rates and other market

forces. Another risk is inefficient management strategies during operation, which can cause

financial losses if productivity of geothermal energy plant declines. The following figure

represents the level of risk corresponding to the stages/activities involved during

development of a typical geothermal project.


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Figure 2: Typical risk profile of a geothermal project (Harvey C 2013)

The risk matrix table below demonstrates the possibilities of occurrence and impacts for the

risks. The red colour on the right hand side means the risks that are more likely to occur and

have a worse influence. In the contrast, the light colour represents risks have lower chance to

occurring and have a lighter impact on the investors. In geothermal projects, the investment is

normally located in the upper right area, indicating higher risk levels. (Deloitte, 2008)

Table 1: Risk matrix table

Not likely Low Medium High Expected

Catastrophic

Significant

Moderate

Minor

Negligible

Likelihood

Co

nse

qu

en

ce


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Risk Mitigation

This section discusses risk mitigation steps to provide fiscal security for investors to

encourage them to invest in geothermal projects. All mitigation steps will be aimed to reduce

impacts of identified risks related to all phases of geothermal projects development. Key

components of risk mitigation are (ESMAP 2012):

a) Availability of sufficiently accurate geothermal resource data and other relevant

information

b) Access to suitable financing and funding structure

c) Condition of project management

Geothermal resource data is deemed vital as the chances of drilling a dry-hole is possible as

discussed in the previous section. Based on Figure 2, it is also identified that the early

exploring phase (Site survey, exploration, test-drilling) carries the highest risk throughout the

project development. Substantial data of the proposed site is crucial in order to minimize this

risk. A proposed mitigation method by Allen (2013) is to establish a database or portfolio of

previous geothermal projects for reference. Information provided should include methods of

drilling and geothermal identification used in order for future development teams to be able

to identify the best methods required to produce a successful geothermal project.

The financing risks involved in geothermal projects, like any other projects with high capital

cost, is extensive. Financing risk is applicable throughout the projects lifecycle. Risk

mitigation is mainly achieved through an interlocked system of contracts between the project

sponsor and all other implementing parties (Battocletti, L 1999). Contractual agreement must

specify responsible parties when any project risks do occur, and whether the projects cash

flow is sufficient to compensate them for the risks they are being asked to bear.

A competent management team is considered an integral part of risk mitigation. The team is

fundamentally responsible for the development of the project within the timeframe specified

which in turn greatly minimise the cost that is caused by risks. These risks include cost

overruns, construction delays, increased construction costs and finance cost increase

(Battocletti 1999). The management team is usually assisted or consist of consultants, service

providers, contractors and construction companies.

Risk mitigation is inexhaustible, similar to the number of risks, and are also unique to each

geothermal projects. However, the main goal of minimising risk impacts can still be

achieved. With a superior risk mitigation plan, geothermal projects will not have any issues to

obtain funding and attracting investors.


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Financial Benefits

With the rapid growth in the geothermal energy industry, New Zealand has become one of

the worlds largest geothermal markets and is known globally for having the highest

geothermal energy production capacity. (Research and Markets, 2013) The major application

of geothermal energy is either to generate electricity or to be used directly to provide heat. It

plays a significant part in New Zealand energy mix and also brings several benefits to the

local economy.

First and for most, the cost of using geothermal energy to generate electricity is relatively

low, comparing with using other energy like fossil fuel and nuclear power. The latest

geothermal power plant can generate electricity for between $0.05 per kWh and $0.08 per

kWh.(NGC, 2013) Also, the costs for electricity generation by geothermal is not dependent

on the changeable market. Therefore, customers are able to have a stable price. Also,

developing geothermal energy can help the country to reduce the amount of fuel imported

from overseas and diversify the mix of fuels relied on.

Furthermore, geothermal resources are more reliable and safer with higher efficiency. Unlike

other renewable energy source like wind and solar power that generate electricity

intermittently, geothermal energy can provide a long-term sustainable solution for electricity

generation. Geothermal power plants are available to operate nearly 95% of time, while the

typical hydro and wind power plants can only operates approximately 50% of time. (EIU,

2012) The Wairakei geothermal power station built in 1958 is the oldest operating

geothermal power station in the world and can still provide a load factor of more than 90%.

(Research and Markets, 2013)

The tables below lists the power consumption and supply of the three main renewable energy

sources in New Zealand, which are hydro, wind and geothermal power.

Consumption (%

of total) 2010 2011 2012 2013 2014 2015

Hydro 11.7 11.6 11.7 11.1 11.1 11.1

Geothermal 21.1 25.2 25.1 29.0 28.9 28.8

Solar/Wind/Other 0.8 0.8 0.8 1.0 1.0 1.0

Table 2: The electricity consumption for renewable energy in New Zealand (EIU, 2012)


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Capacity (mWe) 2010 2011 2012 2013 2014 2015

Hydro 5388 5398 5408 5418 5428 5438

Geothermal 633 738 738 863 863 863

Solar/Wind/Other 646 646 646 821 821 821

Table 3: The electricity supply from renewable energy in New Zealand (EIU, 2012)

From the table, it is clear that geothermal energy consumes the majority renewable power.

Although, other renewable energy sources such as hydro, solar and wind power face

limitations in abnormal weather conditions hence contribution to the total energy production

during these periods is fairly limited. Hydro, geothermal and wind generation account for

over a significant portion of New Zealands electricity supply. The new NZ $1 billion

investment in Ngatamriki and Te Mihi geothermal power plants will add 200 MW of capacity

and increase the geothermal generation to over 1000 MW. (NZTE, 2013) The government

expects that by the year 2025, geothermal energy will produce up to 22% of the electricity in

New Zealand. (Underhill, 2013)

Last but not least, geothermal resources can provide sufficient funds to the local governments

in forms of property taxes and royalty payments. Geothermal power plants are one of the

largest taxpayers in New Zealand. There are almost 70 companies with geothermal expertise

across the value chain, from the design phase to the construction and management phase. For

example commercial development projects such as greenhouses have paid millions of dollars

in tax every year. It also brings job opportunities. There are approximately 400 full-time

employees and hundreds of professional contract workers that are needed for a large scale

geothermal power plant. (NGC, 2013)

The geothermal industry in New Zealand presents an exciting situation and is recognised

globally. As a key member of Geothermal Implementing Agreement, New Zealand also helps

other countries to develop geothermal energy and provide innovative solutions to develop the

downstream industries commercially.


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4.2 Environmental Impacts

Renewable energy resources, such as geothermal power plants are commonly considered as

environmentally friendly since they release low carbon emissions and low pollutants to the

air or water (Burger and Gochfeld, 2012). Indeed, geothermal power production has several

benefits according to the New Zealand Government in 2007 such as: 1) the diversification of

the countrys energy options, 2) dependable base-load power production, and 3) international

leadership in the development of geothermal technology (Barrick, 2007). However, they

also generate environmental impacts that could be dangerous if not managed properly. It is

necessary then to analyze these potential impacts and compare them with other types of

energy generation that are currently important in New Zealand.

Geothermal Energy Generation Impacts

The main impact that geothermal energy plants can generate is related with the extraction

process and the chemicals released. The energy is obtained by excavating wells that are in the

range of hundreds or even thousands of meters of depth (Fridleifsson and Freeston, 1994a).

The fluid obtained is steam, water, or a mix of both which is then separated into steam and

water fractions. In the first geothermal plants, the steam was directed to the power station

while the water was discharged to open waste disposal sites. This process is highly

contaminating since the separated water usually carries toxic chemicals like arsenic, boron,

mercury and silica that damage the natural water bodies that act as waste receptors. Besides

the polluted discharge, this practice also produces subsidence due to the hot fluid withdrawal

which causes a reservoir pressure decline (O'Sullivan et al., 2013). Nowadays, it is known

that the impacts can be prevented by implementing reinjection of the fluid instead of

discharging in the open water. This contributes to sustainability and reduces subsidence

(Fridleifsson and Freeston, 1994a).

In New Zealand, geothermal power plants used to operate without the reinjection method in

the northern island, at Wairakei and Rotorua in the mid-1980s (Fridleifsson and Freeston,

1994a). Here, the unregulated extraction of geothermal energy caused a major damage of

geysers and hot springs (Kelly, 2011). Subsidence achieved its highest value ever recorded

due to underground fluid removal with up to 10 m (Kelly, 2011). This not only affected the

biodiversity and the water receptors but also tourism, which is why the government

implemented control strategies to prevent the environmental impacts. Hence, the government

forced to re-inject the second phase fluid as well as charged for fluid withdrawal (Kelly,

2011). This measure helped to reduce more than two thirds of well discharge (Kelly, 2011).

However, important geysers could not be recovered despite all the efforts.

In terms of biodiversity, geothermal ecosystems contain unique species that are the

consequence of being at more extreme temperatures and chemical spectra than other form of

life can tolerate (Manen and Reeves, 2012). The geothermal environment hosts thermophiles

bacteria known as a biological prospective element (Kelly, 2011). For example, K. Eircoides

is the main endemic geothermal species in New Zealand and it is considered to be at risk


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(Manen and Reeves, 2012). Some of the factors that can alter the existence of this kind of

species are steep soil temperature gradients, soil and water with high content of minerals,

exposure to steam, excess or lack of nutrients and extreme pH conditions (Manen and

Reeves, 2012).

Geothermal energy production, as explained above, implies extracting steam and liquid. The

steam obtained has a content of non-condensible gases such as carbon dioxide and hydrogen

sulphide (Barbier, 2002). Even though the first one (CO2) is the major component, its

emission into the atmosphere is still lower than the ones for natural gas, coal or oil power

station as can be seen in Error! Reference source not found. (Barbier, 2002).

Figure 3 Comparison of carbon dioxide emission from geothermal and fossil fuel-fired

power stations (Fridleifsson and Freeston, 1994a)


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Another gas that is emitted is sulphur but in small quantities which still needs to be

controlled. These emissions are also very low compared to other energy sources as can be

seen in Figure 3. Some removal techniques have been developed such as burning the gas and

transforming it into sulfuric acid that is a saleable product (Fridleifsson and Freeston, 1994a).

Figure 4 Comparison of sulphur emissions from geothermal and fossil fuel-fired power

stations (Fridleifsson and Freeston, 1994a)

To sum up, geothermal power plants can have the potential to cause negative environmental

impacts. It has been shown along the history of the geothermal energy development that the

lack of good technology has destroyed many unique places such as geysers in New Zealand.

Nowadays, there is enough information to prevent these impacts and different mechanisms


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such as the reinjection of fluids are essential. Policy makers have an important role in

protecting the geysers and hot springs. The New Zealand government made decisions that

caused a negative impact to these hydrothermal formations in the early development stage.

Nowadays, it is possible to predict and avoid such impacts especially after the experience of

New Zealand in the Rotoura and Wairakei areas (Barrick, 2007).

Environmental Impact of Different Suppliers of Electricity in New

Zealand It is now necessary to briefly describe the environmental impacts that the two other main

sources of electricity generation cause in New Zealand such as fossil fuels and

hydroelectricity. This is important in order to compare and further understand the benefits of

geothermal energy.

As a general rule, non-renewable sources have negative environment effects since they rely

on finite resources which in many cases are located in sensitive areas; for example, highly

bio-diverse places. Unfortunately in the year of 2012 New Zealand experienced an increase

on the rate of electricity generated by non-renewable sources such as gas, coal and oil. This

was mainly caused by a decrease in the rainfall in the year of 2012 to a historically low

record, which had as a consequence the reduction of 4% from the year of 2011 to 2012, in the

share of electricity generated by renewable sources (Ministry of Business, 2012).

Figure 5 Electricity Generations by Fuel Type for 2011 and 2012


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As it can be observed in the Figure 5 the total share of electricity generated by renewable

sources fell from 77% to 73% in the time period of a year. Another thing that must be

observed is the fact that although having a significant decrease in hydropower electricity,

Geothermal kept growing as it was not affected by the low rainfall season. This enhances the

fact that geothermal as a source of electricity might be a good alternative for New Zealand as

with geothermal with a larger supply of other renewable sources, the country would not need

to rely on fossil fuels as a crucial fuel in back-load and peak supply (Ministry of Business,

2012)).

Fossil Fuel Impacts Fossil fuel power plants produce high environmental impacts in a variety of ways including

water use, land, solid waste disposal, ash disposal (coal) among others. Nevertheless, the

main issue is the emission of pollutants that are responsible for global warming

(VirginiaTech, 2007). In Table 4 a comparison is made between three different methods of

geothermal generation and two fossil fuel sources of electricity.

GASES

RELEASED

GEOTHERMAL

(DRY STEAM)

(lbs/MWh)

GHEOTHERMAL

(FLASH)

(lbs/MWh)

BINARY

(lbs/MWh)

NATURAL

GAS

(lbs/MWh)

COAL

(lbs/MWh)

CO2 59.82 396.3 - 861.1 2200

CH4 0.0000 0.0000 - 0.0168 0.2523

PM2.5 - - - 0.1100 0.5900

PM10 - - - 0.1200 0.7200

SO2 0.0002 0.3500 - 0.0043 18.75

N2O 0.0000 0.0000 - 0.0017 0.0367 Source: (Matek, 2013)

Table 4 - Emissions Levels by Pollutant and Energy Source

As Table 4 and Figure 5 show, the greenhouse gas emissions by geothermal power plants are

much lower than with natural gas and coal. Even though nowadays most of New Zealand

geothermal power has the process of dry or flash steam which has some impacts in gas

emissions, it is still less harmful than other sources of electricity (ContactEnergy, 2011). It is

also important to add that currently there are already two binary geothermal power plants

working in New Zealand which are Te Huka and Wairakei plus another one currently under

construction, Te Mihi power station (ContactEnergy, 2011).


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Hydropower Impacts Hydropower is by far the biggest supplier of electricity in New Zealand as can be seen in

Error! Reference source not found.. Even though the hydropower dams are considered a

renewable source of electricity, their environmental impacts must be taken into account while

comparing to other renewable sources, in this case the geothermal.

It is important to mention that in terms of impacts to the environment, hydropower plants

have positive aspects compared to fossil fuelled plants. They serve as flood control, flow

regulation and they also provide recreation opportunities (VirginiaTech, 2007).

A big impact of hydro power plants is the land use it requires compared to geothermal

energy. They affect the water levels through the length of the river. It is estimated that around

400,000 km2 of land has been submerged worldwide due to construction of dams (Sanguri,

2013). These land impacts may vary widely in function of the topography of the land, the

flatter is the area, the biggest area that needs to be submerged which will incur in more

damage (Sanguri, 2013). Also, some animal species are have been affected with the

construction and operation of hydropower plants such as the Black Stilt, a native bird of New

Zealand which is threaten by extinction due to this hydropower development (BirdLife,

2012).

It is commonly thought that greenhouse gases are not an impact during the operation of

hydropower plants and that these gases are only released during the construction and

operation. However, there are emissions related to the operation of dams which were not

considered before. These emissions will vary accordingly with the size of the dam and the

nature of the land flooded by the reservoir. It has been observed that depending on the

climate conditions, when the area is flooded, the vegetation and soil decomposes and release

both carbon dioxide and methane (UCSUSA, 2013). To make a comparison it is estimated

that life-cycle emissions can be over 0.5 pounds of carbon dioxide equivalent per kilowatt-

hour against a range of 0.6 to 2.0 pounds on electricity generated by gas (UCSUSA, 2013).

In summary, it is clear that the environmental impacts of hydropower are important not only

in considering its implementation during the construction of the dams, but also during its

operation in terms of alteration of wildlife. Also, contrary to what it is commonly held,

hydropower plants release greenhouse gases during operation. The impacts usually are related

to the change in the flow of the river as well as the temperature which might cause aquatic

life to be endangered.


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20

4.3 Social Barriers and Opportunities

More than just providing a clean and renewable energy source, geothermal energy offers

substantial additional benefits to the people of New Zealand. New Zealands unique

geothermal resources have given it an advantage in developing geothermal power

infrastructure and technology. This has fostered a work force, businesses, and educational

institutions with world leading expertise in geothermal technology. In the context of the

Intergovernmental Panel on Climate Changes 5th report, which underlined the need for

action in lowering emissions, low emission energy sources such as geothermal are likely to

become more prevalent around the world. Thus New Zealand has the opportunity to derive

significant benefits from selling its technical expertise and technology. Because of their

experience in developing geothermal energy, New Zealands energy companies have the

opportunity to invest in geothermal projects in other countries. The proliferation of

geothermal energy projects also presents the prospect of increasing the equity of New

Zealand society. This can be achieved through the distribution of revenue generated for the

owners of land above geothermal resources. Many of these owners are indigenous land trusts.

Thus, the development of geothermal energy has and will continue to provide benefits for

Maori people as money from energy projects flows either directly or indirectly to the local

community. It is in these ways that the development of geothermal energy presents an

opportunity to improve the wealth and equity of society as well as facilitating higher levels of

skills and education for New Zealanders.

The opportunity to lead the world The potential for New Zealand to

become a world leader in Geothermal Since New Zealands first geothermal power plant was built at Wairakei in in 1958

businesses, scientists and engineers have gained a great amount of experience in geothermal

energy. The collective knowledge and skills accumulated constitutes a form of human capital,

which can be leveraged to bring benefits for society as a whole. It is predicted that the next

few decades will be a boom time for geothermal energy (Boxer et al, 2013) and the chance

exists for New Zealand to use and grow its knowledge.


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21

Figure 6 - Trial and error at Wairakei, New Zealand has extensive experience in

geothermal energy, taken from Thain, 1998

New Zealand is a world leader in geothermal. It boasts around 70 businesses with geothermal

expertise (NZ Trade and Enterprise, 2013). In addition, institutions such as the University of

Aucklands Geothermal Institute have educated scientists and engineers who work on

geothermal energy projects throughout the world(NZ Trade and Enterprise, 2013). The way

in which New Zealand is at the cutting edge of research and development is demonstrated by

the development technologies such as Joint Geophysical Imaging and 3D Geothermal

modelling (NZ Trade and Enterprise, 2013). Beyond its borders, New Zealands companies

have the potential to invest and gain returns from energy projects in other counties. This is

validated by New Zealand energy company Mighty Rivers investment in geothermal

exploration in Chile(Evans, 2009). In summary, more than just fulfilling its own potential for

the development of geothermal resources New Zealand is well placed to lead and assist the

rest world in exploiting geothermal energy because it has a mature geothermal industry, a

wealth of experience and established educational institutions. Thus there is the potential to

deliver great benefits for New Zealand society, by securing high skill jobs in the booming

high-technology industry.

An exploration of this opportunity can be found in modelling for a scenario labelled the

Energy Revolution by the environment organisation Greenpeace. Greenpeace has estimated

that New Zealand is in the position to reap considerable benefits by capturing a substantial

share the geothermal market. The Energy Revolution Scenario predicts that New Zealand

could capture US$85 to 114 billion of the geothermal market up to 2050 (Boxer et al, 2013).

It also predicts that power from cheap low emission renewable energies such as geothermal


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22

will help to attract energy intense industries to New Zealand, boosting the economy.

However, the modelling underlying the scenario makes ambitious assumptions about the way

in which New Zealand and the world will tackle Climate Change. The modelling makes the

bold assumption that by 2050 New Zealand will have invested NZ$62 billion in renewable

energies (Teske et al, 2013). In a similar way the assumptions made in predicting the demand

and investment in renewable technologies in the Energy Revolution Scenario should also be

scrutinised closely. The predictions are supported by the assumption that within the next

decade oil and coal production will begin to decease dramatically. The modelling sets out that

by 2050 oil production will be around a quarter of what it is today and that production of coal

will be reduced by half (Teske et al, 2013). The reasoning behind these assumptions is that

these reductions are required to avoid potentially dangerous climate change. However, given

the current lack of international consensus and action these assumptions could prove to be too

optimistic. Putting aside the specific details, the Energy Revolution Scenario nevertheless

emphasises that in an increasingly carbon conscious world, New Zealand society is likely to

prosper.

Geothermal: Delivering benefits locally Further to providing benefits to the people of New Zealand through economic prosperity,

individual geothermal projects can also increase the equity of society.

The Maori New Zealands Indigenous People

The ancestors of the Maori arrived in New Zealand some time before 1300AD and lived in

small tribal groups developing a unique culture and religion(Royal, 2013). The arrival of

European settlers in the 19th

century began a period of malaise for the Maori. Conflict and

disease caused turmoil in Maori society and the number of Maori rapidly reduced. After a

period of rejuvenation in the 20th

century the Maori and their culture now hold a prominent

position in the fabric of New Zealand. However, Maori New Zealanders are still more likely

to suffer from preventable diseases and employment and literacy rates are lower for Maori

people than for non-Maoris (Royal, 2013). In an otherwise successful nation, the closing of

the gap between the Maori and the rest of New Zealand constitutes a continuing social

challenge for society.

Closing The Gap a role for geothermal

Much of the land with high quality geothermal resources are located in the North Island of

New Zealand and are owned by Maori land trusts(McLoughlin, 2010). These trusts are be

based around the Iwi groups. Iwi groups are groups of people tracing their decent from a

particular Maori tribe. In conjunction with other activities such as farming and forestry,

geothermal power production can deliver revenue for indigenous land trusts. New Zealands

legal framework is such that the agreement and cooperation of landowners is essential for the


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23

success of geothermal projects (McLoughlin, 2010) thus involvement of land owners in

geothermal projects is essential. There have been numerous geothermal energy projects

constructed on land owned by Maori trusts. However, the extent to which traditional owners

have been involved in geothermal projects has varied. At the highest level of involvement the

trust has formed its own power company. This has occurred on the Mokai geothermal project

where the Tuaropaki Trust in Taupo has set up the Tuaropaki Power Company (Legman,

2001). Other frameworks that exist include joint ventures, such as the one that exists between

the Tai Tokerau trust and Top Energy to run the Ngawha Power plant (McLoughlin, 2010).

These partnerships create wealth for the land trusts and assist them in delivering better

standards of living for Maori people. Land trusts deliver financial and support to members

and the decedents of Iwi groups. For instance the Tauhara North Number 2 trust which was

involved in a joint venture on the The Nga Awa Purua Geothermal Project, provides support

with educational, health and funeral expenses to its seven hundred members(McLoughlin,

2010). This is an example of how geothermal projects can assist in helping to raise the

prospects of Maori people and help to create a more equitable society.

Despite the fact that traditional land owners already benefit substantially from geothermal

projects, scope exists to exploit even greater opportunities. In 2008, NZ$400 million worth of

state forest and money was handed over to a group of 7 North Island Iwi (Hill, 2012).

Consultants have estimated that the Tree Lords settlement provides the opportunity for the

Central North Island Iwi to form their own power company and potentially achieve returns of

NZ$170 - $200 million per year through generating geothermal energy on their land

(Donoghue, 2009). By creating such a company, it was estimated that Maori could be

responsible for generating 10% to 20% of New Zealands electricity within 5 to 10

years(Donoghue, 2009).

Besides financial support, Indigenous involvement in geothermal projects has additional

benefits. The involvement of traditional owners in the development of geothermal projects

helps foster business skills amongst the Maori community. There is also the potential for

environmental and cultural benefits, through the adoption of the philosophy of Kaitiakitanga.

Kaitiakitanga is a key part of Maori culture and embodies a belief that there is a deep

connection between humans and nature. It encompasses the notion that humans have a

responsibility for the protection and guardianship of nature(Royal, 2013). Indigenous groups

have previously used Kaitiakitanga as a structure to address other environmental issues in

New Zealand, such as the management of fisheries(Royal, 2013). An opportunity exists to

extend its use to the resource and environmental management of geothermal projects. This

will assist in preserving and promoting Maori culture while achieving sustainable

management.


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Impacts on Culturally Significant Sites The benefits that the exploitation of geothermal energy provides to Maori people must be

weighed against the potential for permanent changes to existing volcanic features. The

production of geothermal energy at Wairakei has damaged natural geothermal features such

as the depletion of hot springs and geysers(Stewart, 2012). There have also been incidents of

subsidence as a result of geothermal energy projects (Stewart, 2012). Given the significance

of naturally occurring geothermal features to the Maori and their importance to the tourism

industry in New Zealand, the depletion of these assets can be considered to cause serious

cultural and economic damage. However, as the management of geothermal resources has

improved these impacts have decreased significantly.


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5. RECOMMENDATIONS From the analysis above the key recommendations are for:

Increased government support for research and development into technology to

service the geothermal industry. This support should be targeted to keep New Zealand

at the forefront of geothermal development.

Project development should incorporate risk mitigation extensively throughout the

whole lifecycle of all geothermal projects.

Government support for research into enhanced geothermal systems (EGS). (Boxer et

al, 2013). Enhanced geothermal systems are likely to be the next frontier in

geothermal development as they have the potential to broaden the conditions in which

geothermal energy can be extracted. If New Zealand equips itself to be able to provide

support with EGS, then businesses have the opportunity to supply a broader market.

Continued support for educational institutions specialising in geothermal energy such

as the University of Aucklands geothermal institute (Boxer et al, 2013).

An outward looking business focus for New Zealands geothermal industry. In this

way New Zealands geothermal businesses can attempt to secure contracts to perform

work on geothermal projects in other nations.

Attracting the suppliers of the geothermal industry to New Zealand. This could

include encouraging the manufacturers of components used in geothermal systems to

base their operations in designated areas. The obvious location for such a geothermal

hub is Auckland.

Government incentives for indigenous land trusts to become involved in geothermal

energy projects. Such incentives can be justified by the multi-dimensional benefits

they can provide socially and environmentally.

The adoption of a Kaitiakitanga based approach to management of geothermal

resources.

The formation of a Maori energy company made up of the central North Island Iwi

group.

Appropriate available technology to extract geothermal energy has to be used which

minimises the environmental impact that it could cause. The main techniques should

at least include reinjection of fluids to avoid pollution to water bodies and subsidence.

Policy makers have to ensure the protection of geysers and hot springs as well as the

biodiversity that they involve. Episodes such as the ones occurred in the Rotoura and

Wairakei cannot happen again in New Zealand.

Increasing the use of geothermal energy needs to be encouraged from a climate

change perspective since this technology reduces the greenhouse gas emissions.


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26

6. CONCLUSION Economic aspects of geothermal energy projects presented in this report revolves mainly on

the apparent financial barriers of developing projects within New Zealand as well as the

economical benefits related to further pursuing it. Roles of implementing parties and project

investors alike were outlined in order to achieve these benefits. It is evident from the research

done that economic barriers outlined can be overcome provided sufficient support is given

from all parties. The economic benefits are substantial and have the potential to outweigh the

costs associated to financial risks, especially when risks mitigation efforts are carried out.

Benefits from further developing geothermal projects such as providing consistent electricity

at a cheaper cost will improve the livelihood of consumers, contribute to the governments

income and give fiscal profit to investors in the long run. The contribution to minimising

GHG emissions from industrial activities is also significant. It is recommended that the

development of geothermal energy in New Zealand is intensified in regards to its economic

benefits.

In terms of environment, geothermal energy development brings many benefits that need to

be considered. This type of energy has minimum greenhouse gas emissions such as CO2

which are negligible compared to the ones of fossil fuel energy sources. Therefore, this helps

to reduce and mitigate climate change. However, the process that is required to obtain the

buried thermal energy could represent a potential negative impact if it is not managed

properly. This means that technology such as reinjection of fluids to the same layer where the

energy was obtained needs to be applied in order to avoid subsidence and polluted discharges

to open water bodies.

From a social perspective the continued development of geothermal projects and technology

in New Zealand will have overwhelmingly positive impacts. The economic benefits of a

world leading geothermal industry will provide benefits which will flow through to society

by supporting employment and educational opportunities in a high technology industry. The

financial benefits Maori land trusts will receive from geothermal projects will also increase

equity and opportunity for Maori people. Consequently, investing in geothermal represents an

unprecedented opportunity for society to benefit.

Thus, the economic, social and environmental opportunities that geothermal energy presents

are significant, while the barriers and negative impacts are manageable. This makes the

continued implementation of geothermal energy projects and associated activities such as

research a very sound investment for New Zealand.


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27

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Geothermal Energy in New Zealand

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