An Investigation into the Use of Hybrid Solar Power and Cloud

Service Solutions for 24/7 Computing

Emmanuel Kayode Akinshola Ogunshile

Department of Computer Science, University of the West of England, Bristol, U.K.

Keywords: Cloud Services, Solar Energy, Energy Storage, Digital Systems.

Abstract: As the human race demands more from computing, the national grids of nations around the world

subsequently have to burn additional fossil fuels to meet increased power requirements. The aim of this

paper is to investigate ways in which an organisation could reduce its operational costs and therefore be

greener through the implementation of either a complete solar solution or a more hybrid mix with cloud

computing thrown in. Through the creation of a hypothetical UK based SME we compared solar technology

currently in the market in order to understand not only the total investment required but also just how

efficient solar technology is, or perhaps is not. We also investigated comparable technology from the three

cloud providers (Microsoft, Amazon and Google) to discover whether replacing on-premise hardware with

that available in data centres would be more cost-effective than full solar solution or reduce the total amount

of solar technology required. Having conducted the research, we found that solar technology is in no way an

effective solution for the total replacement of power from the national grid, it can be very pricey to

implement especially on the scale of always on computing and is easily affected by the elements-which

given the UK as a location is not ideal. It was also discovered that cloud computing is in no way as

affordable as it is perhaps made out to be but has the benefits of being considered a) an operational

expenditure, b) fully maintained and; c) fully flexible, these all being reasons which help a growing SME

expand down the line without unnecessary hardware outlay. Our final recommendations provide a fair cost

comparison over the total expected payback period for the solar setup of installing a solar solution to power

the entire on-premise systems and simply having a hybrid of both solar and cloud.

1 INTRODUCTION

It was Guntenburg’s modification to the chinese

print press technique that changed the industry

forever with his new approach resulting in over half

a million books entering circulation by the end of

16th century (Whipps, 2008). Fast-forwarding to

modern day and machines of similar technique now

form an industry worth over a staggering $640

billion USD a year (Aleyant, 2015). Whilst the

industry is clearly established you could argue that it

faces an ever increasing threat from the invention of

the 20

century, the internet. With prestigious

organisations such as the Oxford English Dictionary

moving to online-only production (Wang, 2014), this

makes the threat evermore apparent. The Guardian,

on the other hand, disagrees and claims that more

than 80% of respondants still prefer to “consume

articles via print” (Jamieson, 2010). Furthermore,

many printers such as Exaprint have adapted to

provide online-only ordering and production

services which, they claim, result in upwards of 30%

growth year on year (Exaprint, 2015).

In 2005 forty-five trillion pages were printed in

the United States alone (Aleyant, 2015) therefore

creating a demand for machinery that can offer both

increased times of operation and higher production

volume. With many print presses now running 24-

hour operations their business owners are facing an

operational strain in the form of electrical costs.

In this paper we assume the identity of

hypothetical company Bristol Solar whom have

recently entered the bespoke solar market. Their

customer CMYK is looking for a solution to reduce

the operational costs of their on-premise I.T.

hardware through the introduction of solar

technology. Bristol Solar’s specialise in the

deployment of cloud solutions in order to reduce

overall energy consumption. This paper is organised

as follows: Section 2 introduces and discusses the

customer (CYMK) and their existing infrastructure

Ogunshile, E.

An Investigation into the Use of Hybrid Solar Power and Cloud Service Solutions for 24/7 Computing.

DOI: 10.5220/0006380007430754

In Proceedings of the 7th Inter national Conference on Cloud Computing and Services Science (CLOSER 2017), pages 715-726

ISBN: 978-989-758-243-1

715

and section 3 looks at the power consumption of that

infrastructure. Section 4 look in detail at the types of

solar panel technology and how environmental

factors can affect them before finally concluding

which one would suit CMYK. Section 5 presents

information on cloud-computing offerings such as

Infrastructure as a Service (IaaS) etc. and discusses

how CMYK might introduce such offerings and

Section 6 presents the conclusion and cost analysis

of purely converting to solar or employing a hybrid

cloud and solar solution to reduce overall energy

consumption.

2 CUSTOMER SCENARIO

CMYK are a small print organisation with no more

than 30 employees between them yet they each

contribute to the completion of more than 1 million

customer orders per year. Whilst the majority of

employees are warehouse floor staff CMYK also has

your typical back off staff who make use of your

typical Windows operating system to operate the

overall business, from finance to pre-production and

management. In addition, CMYK also operate an on

premise I.T. environment designed specifically for

the storage of customer artwork as submitted via

their online ordering system. You can find a detailed

outline of CMYK’s IT infrastructure in section 2.2

of this paper.

2.1 Recent Capital Investment

Ever since CMYK have moved to online sales they

have seen orders sky rocket which has lead investors

to require that CMYK increase their profibability by

reducing operational expenditure. CMYK are

therefore seeking an energy efficient solar panel

solution to provide 24-hour continuous power to the

in-house server room and have recently replaced all

servers with those that provide more, for less power.

Additionally,

CMYK has done away with typical

desktops in favour of an on-premise, server-driven,

thinclient approach.

2.2 Existing Infrastructure & its

Purpose

CMYK use a combination of Hewlett-Packard

systems and DELL servers each running

virtualisation software such that they operate the

main website, the online ordering system and your

typical Windows Server operating systems. In

quarter one of 2015 alone CMYK had stored

terabytes of historical customer media alone. The

majority of hardware has recently been

introduced/replaced as part of capital investment, see

2.1. In addition to general power efficiency afforded

by solar technology, CMYK are also looking for a

recommendation as to reducing on premise hardware

operational expenditure and have asked for advice

on cloud offerings which, as it happens, Bristol Solar

specialise in. The servers/equipment CMYK

currently use are as follows:

1. HP ProLiant ML110 Gen9 Server, Xeon E5-

2600, 60GB Memory. Used to operate the

majority of print system software and operations

in addition to the hosting of the company’s

websites and order systems.

2. HP ProLiant ML110 Gen9 Server, Xeon E5-

2600, 180GB memory. Used to operate the

compaies terminal services computing

virtulisation. CMYK make use of HP t520 thin

client machines to connect to this server.

3. Dell PowerEdge T110 II compact tower server,

Xeon E3-1200, 20GB Memory. Used to operate

Windows Servers, Active Directory, Print

Servers and general back office systems.

4. HP 3PAR StoreServer File Controller.

5. HP 3PAR StoreServ 8450 Storage unit. In place

to service CMYK’s future storage needs.

2.3 Customer Location

For the purposes of working out solar panel

efficiency, CMYK are located in Avonmouth just off

the M5 in Bristol and have a purpose build building

that is complete with a flat roof surface, perfectly

suited for the installation of solar panels.

3 EXISTING POWER

CONSUMPTION

The aforementioned infrastructure has the following

power consumption requirements expressed in

KWh.

HP ProLiant ML110 Gen9 Servers

0.55 KWh – When looking at the data sheet

provided by HP for their Proliant ML110 Gen9

series server they listed the power requirement for

one individual unit in standard use at 350W. With

that said, no standard power supply unit can

typically provide 100% efficiency and therefore HP

claim 8% power is lost during AC or DC conversion.

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With this in mind, the true power draw for this

machine must be at least 381W. Converting from W

to KWh is as simple as converting from litre to

millilitre. See this equation:

The power P in kilowatts (kW) is equal to the power

W in Watts divided by 1000. Expressed as,

Given CMYK operate two of these systems the total

power is therefore 0.762Kw.

Dell PowerEdge T110 II compact tower server

2.11KWh – According to the hardware datasheet we

know that the PowerEdge T110 II uses between 90 –

264 Voltage AC power depending on use. We also

know that the machine, when converting the power

for its own use operates at 80% efficiency and based

on a UK supply of 240V understand the unit to

require 10 Amp supply. Knowing all of this, it is

possible to convert to KWh using the following

math equation.

The power P in kilowatts (kW) is equal to the power

factor PF times the current I in amps (A), multiplied

by the voltage V in volts (V) divided by 1000.

Expressed as,

HP 3PAR StoreServer File Controller

1.6KWh – The 3PAR StoreServer data sheet

highlights that this controller system makes use of 2

x 800W power supply units encased within the

chassis. This time, however, unlike the HP ProLiant

ML110 we are not provided with any information on

the expected power draw as this varies massively

dependant on the amount of storage devices you

typically install in to the controller. For the purposes

of this research we shall presume the controller

draws with a similar efficiency to the ProLiant

server above and only uses the second PSU as a

backup, using say 10% when idle. Applying the

logic from the calculation of the ProLiant, we arrive

at 736 Watts (main) and 8 Watts (idle). When added

together we get 816 Watts of consumption, espressed

as 0.816 KWh.

HP 3PAR StoreServ 8450 Storage

1.11KWh - It is with this unit where things become a

little more complex. With each additional plug-and-

play hardware device, such as a Fibre Channel card,

comes additional wattage power requirements. In it

is standard configuration the unit can share power

with the File Controller. The unit on its own with no

drives draws 803W of power. 24 drives of a

reasonable capacity (2TB each) draw 13.1 Watts and

a 10Gb/s network card draws 5.71 Watts. Adding

these together we see a total requirement of

1123.11W. Otherwise known as 1.12KWh.

Total Annual KWh Requirements

Based on the above calculations, and the fact CMYK

require their I.T. infrastructure to operate 24 hours a

day, 7 days a week, the total kilowatt power

requirements over a 365-day period expressed as TP

(Total Power) is,

According to statistics published by the (Energy

Saving Trust, 2015), the total average cost per KWh

of electricity in England is 14.05 pence and using

this figure would indicate that it costs CMYK a total

of £5,907 per annum, or £492 per calendar month to

run its I.T. server infrastructure.

4 SOLAR PANELS

In the year 2015 solar panel technology is more

widespread than even half a decade ago and

America’s Fortune Magazine confirms they are not

“just for rich home owners anymore” (Fehrenbacher,

2015). As adoption levels increase, with the UK now

within the global top ten (Solar Trade Association,

2014), so does the differing number of technologies

which satisfy the same goal. In this section of the

paper we take a look at the different types of solar

technology and make a recommendation as to the

most suitied for CMYK.

4.1 Differences in Technology

There are many different types of solar panel

technology in the world but in the mainstream

market there are typically three different types of

panel in use, each with its differing uses. We explore

each of them here with information made available

with thanks to Alternative Technology Association

(herin ATA) and the Energy Informative (herin EI).

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Monocrystaline

Figure 1: Monocrystalline Silicon Solar Cells (Maehlum,

2015).

According to the ATA, Monocrystalline panels are

cut in thin wafers from a single piece of silicon and

all associated conductive cabling is integrated in the

surface of the solar panels themselves. This

therefore produces a very efficient solar panel

which, at the time of writing, EI claim to be the most

effeicent in the entirety of the U.S. market.

EI tell us “Monocrystalline solar panels produce

up to four times the amount of electricity as thin-

film solar panels” and in April 2013 the solar

company SunPower announced their new X-Series

panel. This new panel could produce an average of

21.5% efficiency – one of the highest ever seen from

a panel of this type.

At the time of writing, panels of this type are

widely manufactured by companies such as LG,

Sharp among others. What is more, many of the

aforementioned have faith in their technology by

providing warranties as long as 25 years.

The ATA say that whilst these panels may be

very efficient they certainly come at price but

continue to say that whilst initially expensive they

would pay for themselves within 5 years in most

cases.

For all of their positives though, this type of

panel certainly has one key negative. EI claim that

should only one unit be covered by shade, snow or

anything else it could have an adverse affect on the

energy production rate of the entire collection of

units. However, EI continue to say this affect can be

reduced with additional equipement, a micro-verter,

albeit at increased cost.

EI tell us that Polycrystalline cells often cost less

as a result of a cheaper production process and

according to ATA this panel type is made from

separate wafters of silicon as opposed to one entire

cut, resulting in less chemical waste.

Polycrystaline

Figure 2: Polycrystalline Silicon Solar Cells.

ATA claim that this type of panel has a higher space

efficiency as a result of its square moulded

appareance. By contrast, Monocrystalline are often

more circular and you are therefore unable to house

as many cells within a single unit. Whilst EI agree,

they do say that Polycrystalline’s depedenance on

several silicon wafers as opposed to a single cut of

Monocrystalline significantly reduces the output

effieciency by as much as 8%. Therefore, EI

continue by saying you would require many more

panels in order to compensate for difference you

could otherwise achieve with Monocrystalline units.

It would seem from this research that the

Polycrystalline units, whilst more affordbale, are a

lot less effecient and are perhaps not suitable for a

commercial environment. EI claim that most

concerns they bring up would not really affect

someone in a home, but may be the deal breakers for

business.

Amorphous / Thin Film

Figure 3: Thin-Film Solar Cells.

This type of panel is produced by affixing thin strips

of solar technology on to a substrate such as glass or

metal and according to EI this makes it perfectly

suited to production en-masse. What is more, this

type of panel is not impacted by heat and shading

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issues experienced by Polycrystalline and

Monocrystalline respectively.

EI say that of the three panel types thin film is

the least economical with figures around 7-13%

mark. This would arguably see it much less suited to

an at-home environment. However, with that said,

thin-film is very flexible and as a result can be

placed over a much larger surface area and even in

places traditional panels would otherwise not be able

to go.

Example uses of Thin-Film Solar Cells include

devices such as watches and calculators all the way

up to large-scale solar farms, as pictured.

Recommendation at this Point

Based on CMYK’s initial requirements and flat roof,

Bristol Solar recommends Monocrystaline panels

due to the higher likelihood of seeing a return linked

to their higher efficiency ratings. Whilst they may

initially cost more to install, the consistently higher

energy production rates will ensure CMYK see a

faster return.

4.2 Efficiency Ratings

Understanding which technology is best suited to

CMYK is one thing, but are the panel types truly

efficient enough for the customer’s requirements?

Wind&Sun, a UK distributor of solar panels state

that “Modules nearly always produce less than their

rated peak power in real-life conditions”

highlighting you can not simply rely on a

manufacturers specification sheet alone. So how

exactly do you calculate the true efficiency of a solar

panel? Answering this question will help Bristol

Solar in recommending a suitable panel solution.

Using calculations on the Civic Solar’s website

we can immediately determine the extent to which

solar technology lacks compared with fossil fuel.

The example claims 14.5% efficiency and this

highlights the very important need to research and

shop around to ensure CMYK buy with long-term

efficiency in mind rather than the figure on the

invoice.

The 14.5% system in question has a total input of

1.6KWh from the sun (based on reversing the

calculation), but loses a staggering 85.5% of this in

generating and converting its output 0.24KWh. This

is without taking other facts such as hours of

sunlight, panel elevation and shade in to

consideration. We look at these factors in 4.3.

The efficiency calculation is as follows, where E

is efficiency, W is the manufacturers rating in Watts

and SA equals the surface area of the solar panel in

question.

4.3 Efficiency Factors

Whilst sunlight is one of the only natural resources

that keeps on giving day in, day out, rain, wind or

shine, constant energy generation can not be as

simple as installing it and there must be factors that

prevent maximum energy generation. In this section

we take a look at factors which impact maximum

solar panel efficiency to ensure we can product

installation recommendations.

UK Weather

The existence of the word ‘solar’ in solar panelling

is indicative of a relationship with the sun.

Therefore, deductive reasoning can conclude that

solar panels require the sun in order to function.

Whilst an overcast day might not be very sunny, the

sun is still present and therefore panels do

continue

to function, although at what we presume would be a

less efficient rate of energy production.

We felt it rather important to see just how much

sunlight Avonmouth, the location of the CMYK

facility, received on an annual basis. According to

the Met Office the nearest official weather station to

Avounmouth is Filton, a total of 8 miles away by

road. It is worth noting here that whilst this paper

was written in the years 2015/16, the Met Office

data relates to the 29-year period ending in 2010.

With data spanning such a wide time period it is

more than likely, almost certain infact, that any

averages created from it will vary significantly from

the annual sunlight hours in 2010 alone, or 2015 for

that matter. This is most likely due to changes in

both climate and the angle of the sun since records

began. Nevertheless, the fact records exist in the first

place enables us to improve the findings of our

research investigation.

In Table 1, we can see the total number of

sunlight hours received at Filton weather station per

year is an average of 1627. We can calculate this as

a rounded average of 4 hours of direct sunlight per

day. When comparing the sunlight of Avonmouth

with that of a mainland European city, Barcelona,

there will be a distinct difference. Using data from

Weather2Travel.com we could produce the table

found in the adjacent column.

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Table 1: A table to show the average number of sunlight

hours in the Avonmouth area on a month by month basis.

Month Sunshine (Hours)

Janurary 58.5

February 74.8

March 112.7

April 170.8

May 199.6

June 214.7

July 217.7

August 201.8

September 149.9

October 104.8

November 69.1

December 52.7

Annual 1627.0

Table 2: A table to show the average number of sunlight

hours in the Barcelona area on a month by month basis.

Month Sunshine (Hours)

Janurary 155

February 140

March 186

April 210

May 248

June 270

July 310

August 279

September 210

October 186

November 155

December 155

Annual 2499

You can see that Barcelona receives an annual

average of 2499 sunlight hours. As a rounded daily

average this can be expressed as 7 hours of direct

sunlight. That is a 75% increase over Avonmouth!

With such a stark difference in this figure we can

conclusively say that solar panel technologies will

already be at a significant disadvantage in the United

Kingdom on sunlight hours alone. This is essential

knowledge as with most solar panels producing

energy with at most a 21.5% efficiency rate, every

single hour of sunlight counts if the final solution is

to produce a worthwhile return on investment.

How and why Does Shade Impact a Panel?

To provide the best solution for CMYK we need to

understand why shade impacts a panel and how it

actually does it. In this section shade refers to any time

where the sunlight is not directly upon the panel

surface. This can be caused by overcast skies, or any

object overshadowing a solar panel unit, such as a tree -

although, one would hope a panel never be installed in

close promximiity to a tree in the first place.

There are two definitions for shade on a panel:

soft and hard sources. A soft source is something

such as the shadowing from tree leaves, roof vent or

chimney. Further, a soft source may not be present

all of the time and is usually caused by the suns

position in the sky. A hard source on the other hand

is deemed to be caused by something physically in

contact with the solar panel unit. For example, a tree

branch, a blanket or perhaps an animal/bird sat on

top of it. The same paper continues to say that in

tests of an array of solar panels, simply one unit

being partially hard-shaded drops the power

generating capability of that unit by half and a

completely covered unit would produce no output

whatsoever and actually end up costing money.

Figure 4: A graphic produced to demonstrate the impact

soft-shading can have on an array of solar panels.

A typical installation of solar panels sees units

arranged in series and parallel. According to

research, connecting them in this way enables them

to produce an output voltage and current typical to

most common applications - something a single

panel would not be able to achieve on its own.

During our research, it was observed that whilst

linking panels produces a positive result, it can be

adversely affected in times of shade.

Further, when a cell is shaded, the number of

electrons it can pump from one side to the other

drops. This would not be a huge problem for a single

cell although in most environments units are

interconnected to form arrays. It is in these

situations, that shade has an impact on the amount of

power a units’ neighbour can subsequently produce

too. The output of the shaded unit then becomes the

input of its neighbour. You can see an example in

Figure 4. A completely shaded unit can impact the

efficiency of the entire array by as much as 50%.

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Figure 5: An example solar array with both bypass and

blocking diodes present.

In a separate paper on this topic, H. Patel et al.

produce a software simulation of solar panel

shading. Through various simulations they

discovered that the use of bypass and blocking

diodes, within an array significantly improves its

performance (see Figure 5). The presence of such

diodes sees that units with the poorest performance

are simply bypassed therefore removing the

opportunity for energy loss. Whilst this is great in

theory, MidSummer are quick to say that there are

still many cells within a poorly performining unit

that collect energy exactly as expected. It would be a

shame to simply discount it, they say, and comment

that this is the main reason manufacturers place

diodes at a cell level. As an example let us look at

the 3rd set of shaded modules in Figure 4. A

manufacturer may choose to install bypass diodes at

the tip of the shaded segment thus meaning all

energy generated from cells 16 to 31 simply enter

above the shade of cells 31 to 50. MidSummer

suggest three solutions for solar shade:

1. Install as normal and have poor performance.

2. Act for a smaller array, only installing panels in

areas with consistent sunshine. The cost saved

can be invested in higher effeciency solar panels.

3. Split an array in to smaller arrays by installing an

inverter on each section so to collect and

consume or store the generated energy.

These three solutions are all valid. Which to use

however would depend on the owner of the new

solar panels. In the case of CMYK it would make

sense to follow the latter option as if shade impacted

energy production significantly then it would defeat

the objective of having them in the first place as they

would need to draw from the grid in order to power

their servers. MidSummer say that splitting arrays

costs significantly more as inveters and diodes do

not come at a cheap price. But, it would be a fair to

say you get what you pay for.

Elevation of the sun

With a new understanding of how solar energy is

impacted by shade we felt it important to continue

research in to external factors. The level of shade a

solar panel could experience is most likely itself

impacted by the evevation of the sun. In this section

we will research the elevation of the sun over the

CMYK building and how elevation affects a solar

panel. It is with thanks to the University of

Oregon’s Solar Radiation Monitoring Laboratory,

that I was able to generate a sun elevation graph

using the latitude and longtitude of Avonmouth,

given by Google Maps as 51 degrees, 30 minutes

and 11.9 seconds North and 2 degrees, 41 minutes

and 51.8 seconds West. See Figure 6 for the

resulting solar representation.

Whilst on first glance this graph appears to be

confusing you begin to realise its value rather

quickly once you understand that the y axis is the

suns elevation in the sky and the x axis is the

location of the sun in the sky from east to west.

Furthermore, each red marking indicates an hour of

time and the blue markings indicate the suns journey

through the sky in a given period of time as per the

indicated date. With this new understanding we can

use the data to see that in the height of an

Avonmouth Winter (December) the suns typical

elevations are:

 Sunrise is ~8:30am at elevation 1.5°

 Mid-Morning is at elevation 10°

 Mid-Day is at elevation 12.5°

 Mid-Afternoon is at elevation 4.5°

 Sunset is ~3:45pm at elevation 1°

When comparing this to the height of Summer

(June) we see that:

 Sunrise is ~4am at elevation 2°

 Mid-Morning is at elevation 52°

 Mid-Day is at elevation 62°

 Mid-Afternoon is at elevation 46°



Sunset is ~8pm at elevation 2°

There is of course a huge degree of variance in this

data

Fig. 6. A graph of sun elevation in the

Avonmouth area. Generated using a tool from the

Universiy of Oregon.

from month to month but in picking out Winter and

Summer we can demonstrate, quite clearly, that solar

panels will be significantly affectled in Winter. This

poses the question, where is the best place to install

a solar panel, given this variance in the location of

the sun.

Charles Landau believes he has the answer and

through his research set out to establish the best

installation location with a specific focus on angle of

attack. He tells us that “Solar panels should always

face true south if you are in the northern hemisphere,

or true north if you are in the southern hemisphere”.

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Figure 6.

He claims that doing this ensures every panel

receieves exposure throughout the entire day, as

opposed to only receiving it in the morning if

installed facing eastwards, for example. On it is own

this information is not overly helpful because even

panels installed on flat roofs may be rotated to face

north/south. Thankfully, Landau has this base

covered too and tells us that panels should be

installed at your latitude plus 15° in winter and

minus 15° in summer months. He claims that

adjusting your panels twice a year provides “a

meaningful boost in energy” especially when the sun

is typically lower in the sky.

Armed with Landau’s claims we would therefore

say that effective power generation at Avonmouth

would require all panels to face true south at a pitch

of 66° in winter or 36° in summer. The dates of

change should be March 30th for summer and

September 12th for Winter. Doing this will see

panels generate 74% optimum power. When faced

with criticism over the accuracy of his calculations

Landau states “we are considering the whole day,

not just noon. In the morning and evening, the sun

moves lower in the sky and also further north (if you

are in the northern hemisphere). It is necessary to tilt

less to the south (or more to the north) to collect that

sunlight”. Whilst this is a very valid response

Landau’s admits that should the installation location

be blocked by trees or other buildings etc, then other

calculations will need to be considered. However,

for the purposes of this research paper we will not

discuss those here.

Recommendation at this Point

With all of the findings to this point we can say that

CMYK most effective solution should continue to

consider Monocrystaline panels. Any panels

installed should be both south facing and angled to

calculate for changes in the suns location. What is

more, in order that CMYK can account for poor

performance from shaded panels they should

separate panels in to arrays and make use of bypass

and blocking diodes. In section 5 we will look at a

selection of Monocrystaline panels and discuss

which would be most suitable to CMYK.

5 PUBLIC CLOUD OFFERINGS

5.1 How Much Does It Cost?

Perhaps the most important question here is how

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much does it cost an organisation to move to the

cloud? Well, we have already established in section

7.4 bullet point 3 that there is zero capital

expenditure to move to the cloud – so that is a great

plus for CMYK. Admitedly, CMYK have already

spent a significant amount of money on new

equipment, but even so we shall investigate the

costings involved here. As established in section 7.3,

we compare the cost accross Microsoft, Amazon and

Google where possible.

When deciding which services would suit

CMYK we take a look at their existing hardware

with a specific focus on those which consume the

most energy both now and in the future. From this

we can see that costs could potentially be reduced by

replacing both the Dell server and HP Storage

Arrays. Considering the Dell is a physical machine

offering Windows Server features a PaaS solution

would be approrpaite here. For the Storage Array we

shall look at STaaS.

IaaS – Replacing the Dell

Given that the CMYK have their Dell server

configured with 20GB of memory we shall look at

the next best comparison here to provide at least

20GB as a minimum from each of the providers. The

prices will also factor in a 365-day operation.

 Microsoft Azure

Microsoft offer their IaaS Virtual Machine in a

variety of pre-configured plans. Each plan differs

in processing power and memory allocated to the

VM. Based on the Dell’s initial configuration the

A6 plan is the next most suitable comparison.

Offering 4 processor corses, 28GB memory and

285GB of inclusive storage the hourly pay-as-

you-go rate is £0.4155. The total cost over a 365-

day period is therefore £3,639.78. Whilst 28GB

is 8GB more than currently available, this is

close enough to be considered comparable given

the matching core count.

 Amazon Web Services

Amazon’s take on IaaS is called EC2 but unlike

Microsoft’s offering the EC2 pricing structure

pages can get quite complicated. Nevertheless,

given the requirements of CMYK the closest

matching service is ‘m4.2xlarge’ which offers 8

virtual CPU cores and 32GB of memory. The

hourly pay-as-you-go rate is £0.69 and the 365-

day operation is therefore £6,049 but depending

on whether CMYK require the full 8 cores and

32GB of memory there is a lower plan which

offers 4 cores and 16GB memory, with a pay-as-

you-go rate of £0.34 per-hour and an annual cost

£2,978. Whilst Azure bundles each VM with

some basic storage, Amazon does not do this so

additional storage purchases are necessary atop

of the infrastructure costs, more on how much

this costs in the STaaS heading.

 Google Cloud

Similar to Amazon Web Services, none of

Google’s standard packages suit the initial needs

of CMYK like-for-like. There is a plan below,

and a plan above and prices for both are include

here. The smaller of the two plans ‘n1-standard-

4’ offers 4 cores and 15GB of memory and the

larger ‘n1-standard-8’ offers 8 cores and 30GB of

memory. The pay-as-you-go and annual pricing

for the former is £0.22 and £1927.20 respectively

whilst the latter is £0.44 and £3854. Like

Amazon, these prices do not include any bundled

disk space and therefore this would be as an

additional cost. This is discussed in more detail

under the STaaS heading.

From this comparison of providers, it becomes clear

that Microsoft’s Azure offering is the most suited to

CMYK given its close match to the specification of

the DELL server. The Azure VM is by no means the

cheapest, with one of Google’s offerings being

below £2,000 but we aimed to find the most

comparable offering. In adopting the Azure product

CMYK could completely remove the requirement

for the DELL server and instead transition to

Thinclient operations resulting in an annual saving

of 18,429 Kw from the server alone removing the

need for such to be covered by solar energy.

STaaS – Replacing the Storage Arrays

CMYK plan to store all of their customers’ data on a

storage array offered by HP. Initially it would appear

CYMK’s intentions were to run the storage array

rather empty with only a few drives in operation.

Given the power draw of the drive controllers the

company could offload storage to the cloud and

prevent any future increase in energy demands as

their usage increases. Going back to the research in

point 7.4 we know that cloud services are rather

flexible so CMYK could simply expand their storage

requirements as needed and later shrink them. As for

IaaS we shall compare storage services across all

three providers.

 Microsoft Azure

Microsoft describes their storage offering as

“durable, highly available and massively

scalable” and offers its service with fees based

on the amount of space you truly use, not what

you initially request. The price list is structured

as £0.0147 per GB for the first terabyte per

month followed by £0.0145 per GB for the next

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49 terrabytes per month. So, given CMYK’s

current 48TB usage they would be looking at

£14.70 for the first 1TB and £681.50 for the next

47TB meaning CMYK will be charged £696.20

per month for their current storage requirements

or £8,354 for the year.

 Amazon Web Services

Called Simple Storage, or S3 for short, Amazon

provides three variations on its’ storage product.

Standard, Infrequent and Archive. The former is

a typical storage similar to Azure’s, the latter is

as the name suggests, data archiving and

infrequenty is similar to Standard although

provides lower pricing on the assumption data

will only be accessed infrequently. Given the

requirement of CMYK the Standard offering is

most suitable. Pricing is fairly similar to

Microsoft’s Azure. The first 1TB is priced at

£0.021 per GB with the subsequent 49TB

charged at £0.0206 per GB. It is clear that

Microsoft’s Azure offering comes out on top here

where price is concerned. CMYK’s 48TB would

cost them £21 for the first 1TB followed by

£968.20 making a total of £989.20 per month or

£11,870 per annum. This is a 42% premium over

Microsoft’s Azure offering which is rather

significant.

 Google Cloud

Google’s cloud storage offering somewhat

imitates the exact offering of Amazon in the

sense they offer Standard storage, Infrequent

storage marketed as DRA and Archive marketed

as Nearline. Google also claim they offer “low

cost” storage with no teir pricing. Google’s

Standard offering comes in at a flat rate of 2p per

GB resulting in 48TB costing a total of £960 a

month or £11,520 per annum.

With the comparisons above we can tell that

Microsoft’s Azure storage appears the most

affordable with continued discounts available based

on the amount of storage used thanks to its tiered

offering. It is worth noting that one area that has not

been researched is network traffic. The above cloud

providers each charge for the movement of data

from their data centres across the internet, referred to

as Bandwidth in IaaS terms or Egress when related

to STaaS. Such charges could increase the overall

cost of one provider against another although such

cost investigations are beyond the scope of this

paper.

6 THE FINAL

RECOMMENDATION

Based on CMYK requiring 42,048KW of energy for

a round-the-clock operation Bristol Solar would in

the first instance recommend that the business

reassesses to what extend they would require the

complete 48TB of storage space and based on the

response would recommend one of two possible

outcomes as described under the solution one and

two headings below.

The Panels

We established in section 4.1 of this paper that

Monocrystaline panels provide the edge over

competing technology due to their typically higher

energy ratings and subsequent likelihood for a return

on investment. When it came to the panels

themselves we concluded in section 5 that Sharp’s

ND-F4Q300 offered the most output at 300 Watts

with each unit costing £244+VAT. Section 4.2 saw

us learn that panels should be installed in a southerly

direction in smaller arrays each equipped with their

own bypass and blocking diodes such to attain the

best possible energy generation potential.

Solution One – Keeping full storage & No Cloud

Should CMYK decide to keep the storage hosted

locally then the final solution will need to be able to

provide enough energy for the annual requirement of

42,048KW. This of course includes overnight

power. Based on this CMYK would need the

following (inc. tax):

 141 Sharp ND-F4Q300 Panels (£41,284.80).

 Applicable mount brackets, etc. (N/A)

 8 Lead Acid Batteries (£1,536)

 Applicable convertors etc.

 Installation Labor

The batteries and solar panels will cost a total of

£42,820.80. Based on CMYK’s £5,907 electricity

bill this would take 7 years and 3 months to pay for

itself in savings. As above, £42k is the minimum

cost for this solution. It is highly likely that

additional grid power will also be required should

panels drop below the marketed efficiency.

Solution Two – Using only the Required Storage

If CMYK decide that infact 48TB of data storage

capacity is too much for them then they could switch

to a cloud service provider for the majority of their

storage needs thus removing the requirements for the

HP storage controller and array. This solution also

factors in the removal of the least energy efficienct

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server, the DELL. We established in section 7.4 that

cloud would afford CMYK the flexibility to expand

storage and computing power as required and that

disaster recovery could also be factored in too, if

required. Simply removing the above mentioned

devices from CMYK will see a deduction in their

energy bill of 35,372.88KW or in monetary terms a

saving of £4,969.88 meaning their overall annual bill

would then be £938. Given the new consumption of

6,775.12KW CMYK would then only require the

following (inc Tax):

 23 Sharp ND-F4Q300 Panels (£6734.40)

 Applicable mount brackets, etc. (N/A)

 2 Lead Acid Batteries (min value £1500)

 Applicable convertors etc.

 Installation Labour

The batteries and solar panels will cost a total of

£8,234.40 and based on this solution being designed

to replace £4,969.88 of electricity per year then the

equipment can be seen to pay for itself within 1 year

and 8 months. Costs that are yet to be considered are

those involved in the operation of the new cloud

environment which we established in section 7.4

would cost £5,556.18 per annum with 10TB of

storage from the get go. The new annual cost of the

CMYK I.T. environment would come in at

£6,494.18 per annum after considering the existing

£938 energy cost.

Solution Comparison

Here is the monetary comparison:

 Solution One:

o First Year:

 £42,820.80+ Hardware

o Future Years:

 Depends on any

additional grid power

requirements as on

premise hardware out

grows solar setup.

 Solution Two:

o First Year:

 £8,234.40+ Hardware

 £938 Grid Power

 £5,556.18 Cloud Services

o Future Years:

 £938 Grid Power

 £5,556.18 minimum cost

for cloud services. This

will increase alongside

CMYK’s consumption of

cloud services.

Figure. 9: A graph to compare both the cost of investment

and future costs associated with an all solar solution and

the hybrid solar and cloud offering.

It is worth noting at this point that the first solution

is presuming electrical requirements are not going to

change and that each panel will produce 300W of

energy. This is highly unlikely in the British Isles.

Solution Two is presuming the same, but each panel

is only there to service a small KW requirement by

comparison and the additional electricity charges

would likely be minimal should the grid need to be

called for. However unlike solution one, solution

two provides elasticity from the cloud perspective

and incorporates 10TB of disk storage from the get-

go yet should CMYK uses less then they could bring

this cost down significantly. Cloud computing with

its significantly lower setup costs can also be seen as

a form of operational expenditure (OpEx) which has

the potential to offer tax advantages to CMYK but

those will not be discussed here.

Figure 9 highlights the differing cost of each

solution and it is immediately clear that an all solar

solution has Year 1 costs 190% higher than that

those of the hybrid offering. Although the former

sees a lower year on year cost from Year 2, this will

undoubtedly increase when the solar equipment can

no longer meet future power demands. Whilst a

hybrid setup requires less power from solar panels

for on premise hardware, it has the potential to

become expensive overtime especially when you

factor in redundancy services and bandwidth etc. so

ultimately the final choice would be down to

CMYK’s own budgets. With that said, Bristol Solar

would recommend cloud computing as it would cost

significantly less down the road, enable rapid

deployment and affords so much flexibility down the

road as the business grows.

N.B. Each solution’s’ prices include VAT but would

be subject to change once brackets, cabling and any

associated labour were to be included.

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N.B. Cloud service provider bandwidth/egress is not

factored in to the final price. As a result, any

purchase decision based on this research should

consider this in more detail.

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