Seminar at the Estonian Meteorological InstituteReal-time Monitoring of Mirror Soiling Rates

The Next Generation Ventilation UnitCOST Action ES1002

Newsletter 25

2

Content July 2013

P2: Ben’s Column A Smart Move

P3: News update Seminar at the Estonian Meteorological and Hydrological Institute

¡Hablamos Español!

P4: Automatic Real-time Monitoring of CSP Power Plant Mirror Soiling Rates

P5: The Next Generation Ventilation Unit

P6: WIRE, Weather Intelligence for Renewable Energies, COST Action ES1002

P7: Kipp & Zonen Annual Sales Office Meeting

Visit to the Nigerian Meteorological Agency

Fairs & Events

ContactIf you have a news item for the newsletter or want to

share your experiences with Kipp & Zonen applications

and contribute to our next issues, please e-mail the

editor: kelly.dalu@kippzonen.com

© All rights reserved. No part of this publication may be

reproduced, stored in a retrieval system or transmitted

in any form or by any means, without permission in

written form from the company.

Kipp & Zonen B.V. - 2013

A Smart MoveWelcome to the third quarter edition of our Newsletter. A few

weeks ago the Intersolar Conference and Exhibition in Munich

took place. Intersolar Europe is the biggest event in solar

energy and we used this stage to introduce our Smart Scientific

Solar Monitoring station, based on our SOLYS 2 sun tracker and

enhanced with a Modbus® hub and data logging capabilities.

The move to go Smart is now proven as the right move, a really

smart move. In a nutshell here are the benefits. Compared to

a traditional analogue output the smart interface offers

integrated 24-bit data conversion and the cross-industry

accepted Modbus® data protocol in a standardised RS-485

hardware environment.

The Smart SOLYS 2 collects the data from multiple solar

radiation instruments, and the sun tracker, into a single

Modbus® output. In procurement, a Smart interface equipped

instrument is lower in cost than a classical analogue sensor

with an analogue data logger. It also saves costs in cabling

and in data processing.

Intersolar is a key opportunity to show the capabilities of

Kipp & Zonen in measuring solar radiation. Our Passion for

Precision and our drive to continuously improve our quality

has been rewarded with your loyalty in buying our instruments.

Kipp & Zonen is a leading company in our industry with

ISO 9001 certification since 1995. This gives us a unique

position and for many customers our long term measurement

quality was decisive. Over time quality is priceless.

This newsletter shows many new examples of applications for

our sensors. I hope it sparks your creativity in developing your

own applications. I would like to refer you to our website that

contains many more application examples. We are currently

working on an all-new website that will be launched soon. The

new version will make browsing through our extensive

product list and application notes a lot easier.

I wish everybody a happy summer season with fine weather.

All the best,

Ben Dieterink, CEO

3

The 20 participants came from the Estonian and Finnish

Meteorological Institutes, the University of Science and

Technology of Tartu and the Tallin University of Technology.

During the seminar, presented by our Product Manager Ruud

Ringoir, the principles and optimal use of solar and atmospheric

radiation instruments were explained. This led to interesting

discussions afterwards about critical specifications and the

maintenance of the instruments in general.

After the seminar the Chief Meteorologist showed everybody

around the meteorological site at Tartu. The detailed tour

showed what type of instruments they are currently using.

Some were developed by local scientists, a very small net

radiometer for example.

One of the employees at the Observatory checks, cleans, and

adjusts all the instruments on a daily basis. The adjustment

includes the older one-axis sun trackers that need correction

for the change in solar declination during the year.

Passion for Precision

Seminar at the Estonian Meteorological andHydrological InstituteOn the 23rd of April Kipp & Zonen visited Estonia for a one day seminar about the measurement of solar and atmospheric radiation. The seminar was organized with the help of Timo Berg and Jaan Masik from Perel Oy, our distributor for Finland, Estonia and Latvia. The location was the Tartu Observatory, which is also the main EMHI site for monitoring radiative fluxes. There is a very comprehensive range of measurement instruments and the station has been included in the Baseline Surface Radiation Network (BSRN) since 1999.

The Spanish website is a copy of the international, English,

website with the same information; product details such as

the descriptions and specifications, a selection of application

stories that explain the various possibilities for our instruments,

and corporate information about Kipp & Zonen and how to

contact us. The quote request functionality makes it easy to

contact the right distributor for your inquiries.

To have a look a look please visit our new Spanish website

directly www.kippzonen.es

¡Hablamos Español!Over the years we have seen a growth of visitors to our website from the various Spanish speaking countries. We are happy to announce that we can now cater for this group in their own language! As of now the Kipp & Zonen website is not only available in English and French, but also in Spanish.

We would like to thank all the participants and Perel Oy

for the interesting visit and great opportunity to share

information. We returned home with good feedback and

ideas for the future.

Find out more about EMHI at www.emhi.ee and the Tartu

Observatory at www.aai.ee

With thanks to our distributor for Finland, Estonia and Latvia

- Perel Oy, www.perel.fi

4

Once a power plant has passed commissioning and is running

at the best possible level, from the engineering point of view,

one of the most efficiency-limiting parameters is the decreasing

cleanliness of solar reflectors and receivers caused by soiling;

i.e. the accumulation of dirt (aerosol and sand particles, dust,

biological matter, etc.) on their surfaces. This can cause weekly

efficiency loss well above 10%.

The losses due to soiling of power plant components are

reduced by cleaning. However, cleaning causes an increase

in maintenance costs and water use, even when using

sophisticated robots. Therefore researchers and maintenance

teams at power plants are aiming at cost optimization for

cleaning strategies. The currently employed soiling measurement

methods allow only very few measurement points in time and

are rather tedious. As measurement methods improve, the

effects of different mitigation strategies can be studied in more

detail, taking into account the highly non-linear behavior of

soiling characteristics

.

TraCS stands for Tracking Cleanliness Sensor. A precise solar

monitoring station that is already used in resource assessment,

or in a running power plant, serves as a basis for the installation.

It consists of a sun tracker with two pyranometers for measuring

the diffuse and global horizontal irradiances (DHI and GHI) and

a pyrheliometer for the measurement of direct normal irradiance

(DNI). The TraCS installation adds an extra accessory to the

tracker, a second pyrheliometer looking backwards into a mirror

that reflects the DNI back into the pyrheliometer.

Dividing the reflected DNI signals by the directly measured

DNI signals gives the reflectivity of the sample mirror.

Normalizing this to the value measured with a clean mirror

gives the parameter of cleanliness in real-time whenever the

sun is shining.

TraCS is a new and accurate measurement system for the

cleanliness of solar mirrors, with the advantage of using the

natural sun spectrum and measuring at a high time resolution.

It has been validated successfully and the limits for the best

measurement conditions have been determined. It can be

adapted to specific power plant conditions regarding the

acceptance and reflectance angles. A correlation of the soiling

to other weather parameters measured simultaneously at the

same site will pave the way to a more global understanding of

this poorly investigated parameter.

Furthermore, the TraCS accessory can be used to improve the

quality of the main DNI measurement of the station respective

to the cleanliness of the main pyrheliometer entrance

window. This can be detected easily for later correction, even

if the sun was not shining during the cleaning of the sensor.

TraCS was designed by DLR and installed at the Université

Mohamed Premier in Oujda, Morocco. It has been optimized

for more reliable output at the Spanish Plataforma Solar

de Almeria (PSA) and is commercially available from the

DLR spin-off company CSP Services GmbH in Cologne,

www.cspservices.de

Source: ‘A Novel Method for Automatic Real-Time Monitoring of

Mirror Soiling Rates’ by Fabian Wolfertstetter, Klaus Pottler,

Ahmed Alami Merrouni, Ahmed Mezrhab and Robert Pitz-Paal

Automatic Real-time Monitoring of CSP Power Plant Mirror Soiling RatesTraCS is a new measurement system that allows for an easier, more precise and more effective measurement of the soiling level of solar mirrors. It is the outcome of a collaborative study by the German Aerospace Center (DLR), Institute for Solar Research and the Université Mohamed Premier of Oujda, made possible by the Morocco Meteonet Solar Project. Kipp & Zonen instrumentation was used for the testing to have a precise solar monitoring station with well-established equipment.

Kipp & Zonen Solar monitoring station with TraCS accessory

The full paper can be found on our website at

www.kippzonen.com/soilingrates .This paper received the Desertec Best Paper Award in 2012.

The award is organized by the Desertec Industrial Initiative,

together with the Desertec University Network and aims to

recognize outstanding academic work related to the

development of renewable energy in Europe, the Middle East

and North Africa. Find out more at www.dii-eumena.com

5

Passion for Precision

The Next Generation Ventilation UnitEven the best can be improved. Kipp & Zonen launches the CVF4, a much improved ventilation unit for the pyranometer and pyrgeometer range to replace the very successful CVF 3 that has been in production for over 5 years, and was itself an update of the CV 2.

Ventilation of radiometers improves the reliability and

accuracy of the measurements by reducing dust and

precipitation of dew on the dome, which would otherwise

affect the measurement. It stabilizes the temperature of

the radiometer near to that of the ambient air and

suppresses the thermal offsets which are produced by

cooling down of the domes under calm clear sky conditions

or by dome heating due to absorption of solar radiation.

Heating of the air flow evaporates water droplets and melts

frost, snow and ice.

The CV 2 and CVF 3 were designed empirically and are

amongst the best ventilation units available. However, by

using the latest flow simulation software and micro flow and

temperature measurement devices to check performance,

significant improvements were made. On the instrument

dome the flow was measured at 17 points and in 8

directions. This work has resulted in a new and much

improved ventilation unit, the CVF4.

The axial fan of the CVF 3 has been replaced by a centrifugal

one, giving a much higher air pressure. At the top of the

pyranometer dome the flow of the CVF4 is actually 4 to 5

times higher than on the CVF 3 and it swirls to improve the

distribution over the dome. There are two heaters, raised

inside the housing so that the air flow is warmed close to the

exit point and less heat is dissipated into the base. The CVF4

cover is moulded plastic (instead of pressed aluminium on

the earlier models), which reduces the heat loss. The

combined effect is that the same performance is maintained

with only half the heating power.

Two captive knurled screw knobs make it easy to remove the

cover without tools to check the radiometer desiccant. Like

the CVF 3, the pulsed tacho-output to monitor fan performance

and a waterproof connector and yellow cable are standard.

The CVF4 is solidly fitted to a mounting, or sun tracker plate,

and then the radiometer is fitted to it and leveled using its

own adjustable feet. This is simpler that the system with the

CV 2 and CVF 3 where the radiometer feet are removed and

leveling is done by the ventilation unit, which must then be

tightened down without disturbing the radiometer position.

Because of the centrifugal fan, the air inlet is no longer

directly under the ventilation unit. It is now beyond the rear

of the tracker mounting plates so that it is easier to replace

the inlet filter and prevents leaves or snow collecting under

the filter.

Cable lengths of 10, 25 and 50 m are available or it can be

supplied with the connector plug only, for the customer to fit

their own cable. CVF4 is designed to operate under all

weather conditions and is easy to use. The only part that

needs maintenance is the removable air inlet filter, which

should be checked at regular intervals and cleaned or

replaced as necessary. A ventilation system does not

prevent the dome becoming dirty, but it can significantly

reduce the frequency of manual cleaning.

CVF4 is designed to be used with Kipp & Zonen CMP 6, 11,

21, 22 and SMP11 pyranometers, the CGR 4 pyrgeometer and

the CUV 5 total UV radiometer. It is possible to fit the CMP 3,

SMP3 and CGR 3 into the CVF4 but the improvement is rather

less due to the small dome size within the cover outlet, so

the air pressure is lower. CVF4 is backwards compatible with

the older CM, CG and CUV radiometers.

CVF4 can be mounted on the 2AP and SOLYS 2 sun trackers

(up to 3 units on one tracker) and the CM 121C shadow ring.

It is a direct replacement for the CV 2 and CVF 3 models.

The CVF4 ventilation unit runs from 12 VDC, the fan takes 5 W

and the heaters take 5.5W. The tacho-output pulse is nominally

5 V. The accessory CVP 2 universal AC-DC power supply can

operate up to two CVF4 ventilation units with the heaters on.

CVF4 replaces the CVF 3 in our product portfolio and will be

available in the third quarter of this year.

The ISO Technical Report 9901:1990 ‘Solar Energy - Field

Pyranometers Recommended Practice For Use’ contains an

informative chapter on ventilation systems in general

6

WIRE, Weather Intelligence for Renewable Energies, COST Action ES1002Kipp & Zonen at the Summer School ‘From Renewable Energy Production to End Users’ at Montegut, France in July 2013.

What is COST? COST is an intergovernmental framework for European

Cooperation in Science and Technology, coordinating

nationally-funded research on a European level, in which

various national facilities, institutes, universities and private

industry jointly work on a wide range of R&D activities. COST

provides financial support for travel, organising meetings,

project administration and reporting, but does not contribute

to executing R&D activities.

WIRE, Weather Intelligence for Renewable Energies, COST Action ES1002The generation of wind and solar energy is strongly dependent

on highly variable weather processes, which can lead to

strong fluctuations in the supply of this electricity into the

grid. Proper and specific forecasting of ‘energy weather’ is

key to forecasting such variations and to manage them

properly. In COST Action ES 1002 (started in 2010), also

known as WIRE (Weather Intelligence for Renewable

Energies), www.wire1002.ch, these topics are addressed.

WIRE has two main activities; firstly, to develop

post-processing algorithms for weather predictions to

obtain optimised forecasts for wind and solar energy

production using meteorological observation data and,

secondly, to investigate the relationship between the highly

intermittent weather dependent power production and the

energy distribution to end users.

The first activity in the action was a State of the Art

Workshop, held in March 2011 in Nice, in order to bring

together the scientific and industrial communities, and to

assess the requirements issued by the power plant managers,

the operators and the electrical grid specialists. This meeting

helped to characterise and assess the methodologies, which

led to the ‘State of the Art’ report in August 2012 providing

an overview of the renewable energy activities in the

participating countries. In 2012 MeteoSwiss organised an

inter-comparison in which several instruments for measuring

solar radiation for solar energy plants were compared. The

inter-comparison of the weather prediction models with

post-processing is on-going.

Summer school ‘From Renewable Energy Production to End Users’, July 2013In collaboration with the 2nd International Conference on

Energy Meteorology ICEM, www.icem2013.org, WIRE is

organizing a Summer School ‘From Renewable Energy

Production to End Users’ from 1 to 5 July, 2013, in Montegut,

about 100 km away from Toulouse in the French Pyrenees. It

aims to provide basic and advanced knowledge on the

forecasting of Renewable Energy production for wind and

solar energy and its applications.

Impacts of variable electricity generation sources

The program covers topics such as renewable energy

forecasting and climate, basic meteorology, numerical

weather prediction and high resolution mesoscale models,

forecasting of wind and solar energy production, uncertainty

in power forecasting, measurements dedicated to renewable

energies, etc.

Kipp & Zonen is involved through sponsoring of the summer

school, and Kipp & Zonen’s Business Development Manager,

Dr. Foeke Kuik, will give a lecture at the summer school with

the title ‘Solar Energy Related Measurements’. Dr. Kuik is

also the chair of Working Group 2 of the action, called

‘Measurements and Validation’

Wind PowerHighly variable, difficult to predict.Causes increases in spinning reservegeneration, and risk of grid instability

Transmission & distributionTemperature, humidity and wind impact line capacity.Weather is largest cause of outages (lightning, high winds, ice,transformer failures due to high load, etc.)

Solar PowerSolar contributions can cause

system instability due torapid cloud cover changes

Load ForecastingDemand variation due to

weather

Passion for Precision

7

Kipp & Zonen Annual Sales Office MeetingOver the 16th to 18th of April the three sales offices of Kipp & Zonen were invited to the headquarters in Delft for the annual sales office meeting. Although you can discuss lots of things using phone, e-mail and WebEx, the chance to meet in person, share ideas and have some fun as well, is not to be missed.

The offices presented their results and their outlooks on the

most important projects and markets.

Our French office will focus more on expanding our distributor

network in Northern Africa and Arabia, as solar energy is

growing rapidly in these countries. Kipp & Zonen will have a

booth at the Gulfsol exhibition from 3rd to 5th of September 2013

in Dubai, which is an opportunity to meet with both customers

and potential distributors. Another exhibition that our French

colleagues look forward to is the EU PV SEC in Paris in October.

The USA sales office is going strong in the more traditional

meteorology market of Kipp & Zonen, as well as in the solar

energy market. Solar plants in the USA tend to be larger than

anywhere else in the world, which provides us with interesting

opportunities. The entire team could not attend the sales office

meeting, as we also had a booth at SOLAR 2013 in Baltimore.

The office in Singapore manages the Asia-Pacific region, which

is continuing to grow strongly. In addition to presenting the

sales figures, the preparations for the 2013 International Sales

Meeting were discussed, which is to be held from the 2nd to 4th

of October in Taipei, Taiwan. As in other regions, Kipp & Zonen

was represented at several important exhibitions, including the

SNEC in Shanghai in May and the Renewable Energy Asia

exhibition in June in Bangkok.

From the head office in Delft ideas and progress on new

product development were shared, as well as the company

results so far. The meeting would not be complete, without a

good outing in a typical Dutch setting, so we made a boat trip

on the river Maas in Rotterdam with sunny weather and only

some moderate waves. The boat however was a taxi, and the

captain felt obliged to bring us as swiftly as possible from A to

B to C. So we held on to our seats and then hopped on and off

to see some sites close up, like the historic windmills at the

Kinderdijk. The day finished with a dinner at the restaurant Kip

(and no, we did not cook ourselves).

All in all, a worthwhile and enjoyable 3 days, which helped us

to catch up on our business worldwide and continue our

teamwork in expanding the Kipp & Zonen footprint

Visit to the Nigerian Meteorological AgencyThe Kipp & Zonen CFR Calibration Facility offers customers the means to perform factory-standard calibrations of pyranometers and albedometers. The Nigerian Meterological Agency (NIMET) has purchased a CFR and Kipp & Zonen recently visited the capital, Abuja, to install it and provide customer training.

Our equipment and method is specifically referred to as the

‘Kipp & Zonen Device and Procedure’ in Annex A.3 of international

standard ISO 9847 ‘Calibration of Field Pyranometers by

Comparison to a Reference Pyranometer’. Installation and

training at the customer site by Kipp & Zonen is required to ensure

that calibrations are carried out in accordance with the standard.

NIMET has constructed new calibration laboratories at its

headquarters close to Abuja International Airport, including a

separate air-conditioned dark room with uninterruptable power

supply (UPS) for the CFR. NIMET has an increasing number of

Kipp & Zonen CMP 3, CMP 6 and CMP 11 pyranometers.

During the four-day visit by our Customer Services Specialist, Clive

Lee, the equipment was installed and commissioned and a training

course on the maintenance and operation of the CFR given to NIMET

staff. The opportunity was also taken to provide a half-day seminar

on solar radiation measurement and solar energy applications.

We would like to thank NIMET personnel for their enthusiasm and

hospitality, and we look forward to working with them in the future.

With many thanks to our distributor for Nigeria, Alifig International

Ltd, of Abuja, who supplied the equipment to NIMET and provided

much assistance during the visit. Find out more about NIMET

www.nimetng.org

Fairs & EventsGulfSol 2013 • Dubai • UAE

EMS Annual Meeting • Reading • UK

EU PVSEC • Paris • France

Meteorological Technology World ExpoBrussels • Belgium

Solar Power InternationalChicago • USA

APVIA PV Asia Pacific Expo 2013Singapore

3 - 5 September

9 - 13 September

1 - 3 October

15 - 17 October

21 - 24 October

28 - 30 October

4414125-1307

Go to www.kippzonen.com for your local distributor or contact your local sales office

Passion for PrecisionKipp & Zonen is the leading company in measuring solar radiation and atmospheric properties. Our passion for precision has led to the development of a large range of high quality instruments, from all weather radiometers to complete measurement systems.

We promise our customers guaranteed performance and quality in; Meteorology, Climatology, Hydrology, Industry, Renewable Energy, Agriculture and Public Health.

We hope you will join our passion for precision.

HEAD OFFICE

Kipp & Zonen B.V.Delftechpark 36, 2628 XH DelftP.O. Box 507, 2600 AM DelftThe Netherlands

T: +31 (0) 15 2755 210F: +31 (0) 15 2620 351info@kippzonen.com

Kipp & Zonen Asia Pacific Pte. Ltd.10 Ubi Crescent Lobby E#02-93 Ubi TechparkSingapore 408564

T: +65 (0) 6748 4700F: +65 (0) 6748 6098 kipp.singapore@kippzonen.com

Kipp & Zonen USA Inc.125 Wilbur PlaceBohemiaNY 11716United States of America

T: +1 (0) 631 589 2065F: +1 (0) 631 589 2068kipp.usa@kippzonen.com

Kipp & Zonen France S.A.R.L.88 Avenue de l’Europe77184 EmerainvilleFrance

T: +33 (0) 1 64 02 50 28F: +33 (0) 1 64 02 50 29kipp.france@kippzonen.com

SALES OFFICES