Euro SUN 2000The third ISES-Europe Solar Congress

Visions for the new millenniumJune 19-22, 2000

Copenhagen, Denmark(Paper presented for oral or poster presentation on applicable subject no 3&5. PV-thermal-in buildings)

Building Integrated Multi pv/t/a Solar System roof tileEng. Ami Elazari MBA

Millennium Electric t.o.u. LTD p.o. box. 16007 Tel Aviv 61160 Israel.Phone 972-3 –5234776 Fax 972-3-5248945 e-mail solor@netvision.net.il

AbstractPrevious development in solar energy for residential applications proved that there is merit infurther development and improvement of combined electricity and hot water and hot aircollectors. The justification stems from the fact that waste heat is generated when PV cells areproducing electricity but it decrease its efficiency dramatically, and any effective way to cool thecells can improve their efficiency and long while the heat that generated from this coolingprocess could be stored and used as standard solar hot water /air system.The "core" unit comprises of integrated PV cells mounted on a flat-plate collector for water andair, hot water storage tank hot air inlet pips to the house electric battery bank, inverter,connecting cables and controller. Double-glazing serving as "solar trap" to triple the amount ofsun ray reaching the PV cells and other technical innovation make the system more cost effectiveand cost benefit for stand alone and grid connected domestic application. --Two -wayinterconnection with the electric grid like in all the "roof top program" may bring it to economicviability by selling excess electricity during the costly peak hours while buying low costelectricity during the night off-peak hours, and free electricity from the sun plus free hot waterand hot air for domestic use as by-product.A basic domestic two-collector system may deliver up to 4 kWh of electricity and 12000 kcal ofhot water and air daily. Some 29 systems are currently operating at various locations in Israel,some for 8 years with very good results. Us patent 5522944 (www.uspto.gov)

Application and benefits-purpose of theworkPhotovoltaic electricity supplying haveproven as viable and longevitycharacteristics, practically maintenance freeand could be coupled with quality flat-platecollectors to give over 15 years of trouble -free operation, providing electricity and hotwater and hot air for domestic applications.These multi solar systems could serve bothstand-alone and grid connected applicationwith 7 cents/kWh or less energy cost.

Substantial saving can be realized in massproduction manufacturing and in multimodule centralized installations. With theanticipation of further reduction in PV costthe multi solar system can become evenmore cost -effective in world markets, withtechnology transfer possibilities to lessdevelopment regions in the Mediterranean,middle east Asia and Africa.

Scientific innovation: - multi solarroof tile the ultimate brick stone ofthe 21st century

This proposed innovation derives from thesame ~core' unit of the multi solar system,but it is not just a fiat-plate combined solarcollector like we have in mass and spreaduse in Israel but to developed multi - rooftile or facade block That will be integratedin to building~ roofs and facade. Therational for such development is botheconomic and esthetic and solar wise right.There is a window of opportunity of suchdevelopment according to the prospect of 5millions rooftop programs all over theworld.The main rational for this product is that ifyou calculate the pay back time of a stand-alone PV only system in the field, the payback time is about 16-18 years. If you do arooftop integrated PV only system the payback time drop down to 12 yeas. If you addone more function to the above integratedrooftop facade system like introducing hotair for space heating to the house, the payback time drops to 7 years. And if you addhot water production for the same integratedsystem the pay hack time drops to 3 years,which is an economic figure of: 5-7 centsper energy unit cost.

The Multisolar PV/T/A System

IInnttrroodduuccttiioonn

The MULTI SOALR PV/T/A is an innovative co-generationsolar device that makes it possible to convert solar energyinto thermal energy and electric energy at the same timeusing a single integrated system.

This new technology is under development in the frameworkof a EUREKA / CORDIC/ OPET project supported by theEuropean Commission, and expected to last until June 2001.

11.. WWhhaatt iiss tthhee MMSSSS PPVV//TT//AA ssyysstteemm??

The MSS PV/T/A system is a totally new kind of solar energyharvesting device, formed by the coupling of:

1. PV modules capable of collecting the visible spectrum ofthe light; integrated into flat plate hot water modulesbased on any commercial technology.

2. The Multi solar system, an innovative patented solarPv/thermal system that collects boath the visibale &infra_red side of the spectrum, cools the PV cellgenerate electricity and makes the heat available forthe thermal control of the building; The MSSPVTA ismade of Façade rooftile panels, behaving like a“living”skin surrounding the building, where a water/airflows, capturing heat, storing in an insulated tank andmaking it available for heat control of the livingenvironment.while the pv cell generate electricity fordomestic use.

3. Structural building elements (like panels or tiles); thesystem has been designed to withstand a structuralfunction, being for instance the covering roof or thewalls of a building.

In MSS panels, PV modules are integrated on the freesurface of conventional DHW flate plate panels exposed tothe highest solar radiation, placed on the roof of thebuildings, and are fully integrated with all necessaryelectronic power components.

The MSSPVTA system is the integration of the PV cells withan innovative solar heating device (PATENT NO 5522944),that makes it possible to exploit solar energy to produceElectricity and Heat at the same time, using a single device.This new innovative system, for instance, installed in ahouse, allows to produce electricity and provide energy tothe electric appliances; however it is possible to provide heatfor water and air space warming and also to store it so thatit can be used during the cold seasons.

However the MSS provides another advantage, by couplingthe two devices, the PV system and the Thermal. It allows toreduce the operation temperature of the PV cell thusincreasing the operational life, particularly in relation to thethermal stress of the mechanical structure of the cells. Infact, the MSSPVTA makes possible the circulation ofappropriate water and air beyond the PV cells, thusimproving the efficiency of the cell and collecting heat like atraditional solar-thermal element.

22.. TThhee MMSSSS PPVV//TT//AA ssyysstteemm cchhaarraacctteerriissttiiccss

The MSS PV/T/A is a Ami Elazari patented invention, ainventor strongly engaged in the fields of active solararchitecture and photovoltaic systems. (patent no 5522944see also www.uspto.org on the name of ELAZARI more 20patents)the mss is a fluid-transfer, thermal energy captureconcept, made of panels with a double air/liquid reversiblecircuit used for heat/cold transfer. It allows the walls,windows and roof of buildings to capture thermal energy andassist in maintaining the interior environment of the buildingcomfortable for humans to live and work.

The thermal efficiency of the water system is about 40 %.

The thermal efficency of the air system is about 40 %.

The electrical efficency of the PV system is about 14 %.

The MSS PVTA offers the unique capacity to collect ENERGYfrom the sun, to tore it, even for long periods of time and

redistribute it through the building according to the comfortneeds to the various areas within the building. In hotweather, the MSS PVTA ROOF TILE AND FACADE maintainthe right temperature by capturing the excess heat andcarries it away, while circulating fresh air and liquid throughspecially designed panels around the structure of thebuilding to provide cooling.

The electricity produced by the PV cells stored in a batterybank usualy placed underground in the basment of thebuilding or under the roof. The DC battery bank is connectedto an DC-AC inverter/charger that connected to the mainbuilding electricity control box .it can provide all theelectricity to the building and sale and buy electricity to andform the electric grid.

Heat is transferred by the water & air to the tank, usuallyplaced underground in the basement of the building, inwhich stone containers stored the heat as the fluid comes incontact with them.

The Tank is a specially insulated reservoir, allowing thestorage of heat also for long periods; this is allowed also bythe special stone containers, immersed in the tank, whichcan multiply the heat storage potential of the regular DHSwater tank.

The heat stored in the stone can be used to produce hotwater and with a fluid & air reverse movement used forhouse heating; this means that the heat stored in the tankcan be used to heat the interior environment during the coldseason (low temperature heat, wide internal exchangesurface), with no need of supplementary heat integration atwarmer latitudes.

The multi solar rooftile/facade has been developed alsoalong a very innovative and unique feature.

Beyond flate plate hot water panels, special double glassPV panels have been developed; the AIR WATER fluid flowswithin the two water/air pipe channels, capturing theinfrared radiation, but allowing the visible spectrum to flowthrough, lighting the interior environment.In this way thesame window can become an active element capable toprovide,electricity beyond lighting, and heat control.

The MULTI SOLAR SYSTEM is actually successfullyexperimented and 7 buildings have been built equippedwith MSS since 9 years. The MSS can works with circulatingair, and it is fitted with automatic valves for interiorventilation with filtered and humidified air using small fans.It is integrated in the outer shell of the building andproduces zero oxide or dust emission.

A 10 m2 solar/thermal roof/façade is being developed; itwill see the integration of commercial mono-crystallinesilicon devices.

33.. TTPPVV ssyysstteemm eeccoonnoommiicc aannddeennvviirroonnmmeennttaall aaddvvaannttaaggeess

The MSSPVTA will form a part of the structure of thebuilding, covering walls or roofs in a natural way, not beingsomething added. Its role as structural material will have agreat impact due to the fact that it will effectively replaceparts of the building, with the cost reduction that this willentail.

The economic potential of the MSSPVTA system lies in itsinherent global high efficiency; the same device reaches atotal efficiency (PV + thermal) of more than 70%, thus beingable to exploit more than the half of the energy radiatedfrom the sun.

Therefore, with a single installation, a highly integratedsystem can supply:

ü Electric energy

ü Thermal energy, allowing to substitute not only waterheaters but also conventional building heating plants,thanks to the low temperature heat which is radiatedby TS panels and extracted by the tank.

ü Be a structural element of the building (wall or roof); itwill replace parts of the building like walls and roofs,which will save money during construction. That willallow to minimise the pay-back time of the investment(including substitution costs)

On the overall, the MSSPVTA concept is a revolutionarysystem which can allow pay back periods even in the orderof 3 to 7 years. The replacement of substantial amounts of energy fromtraditional sources by this environmental friendly, renewableenergy source will produce a big environmental impact dueto the saving of tons of fuel and the reduction in the same

proportion of the emissions of gases to the atmosphere.

Attached data results and conclusion:1. Household consumption table2. Economic rational for integrated multi solar

system3 system drawings&pic.(see attached jpg files fordrawings and system pictures)4. Cost comparison between PV sys. Hot water sys.

And multi solar sys

Domestic Electrical Consumption

(FROM WORLD BANK DATA)

ÖBHB

Single personhousehold

�

Two personhousehold

��

Three personhousehold

���

Four personhousehold

�Lighting 150 250 320 380Electric stove 210 410 470 590Refrigerator 350 390 440 530Freezer 280 470 570 780Washing machine 100 190 280 380Clothes dryer 100 170 270 370Hot waterBathroomKitchen

34060

71080

1020100

1300120

Dishwasher 100 210 280 380Television set 100 130 170 220Auxiliary devicesfor centralheating

350 400 450 500

Others smallappliances

290 450 520 600

consumption perhousehold day 3.4 kWhd 7.6 kWhd 10.6 kWhd 12.3 kWhd

The Economic Rational For Installation Of ABuilding- Integrated Multi Solar System

� The following table clarifies the economic advantage of a building- integrated Multi SolarSystem. The table includes current prices and costs.

� The multi solar system performs three functions; photovoltaic electricity, water heating andspace heating.

� Even at today’s fuel prices this system is competitive and cost efficient.

EnergyCost/Production

TotalProduction/

Cost

Cost OfHot Air

Cost OfHot Water

Cost Of PV Cost OfBuilding

/M2

Size OfWall Or

Roof.TotalCostIncludingBuilding

$ 850 $ 50 $ 100 $ 600 $ 1001m2 multi

solarsystem

Peek-TimeProduction PerM2

750 Wp 300 Wp 300 Wp 150 Wp ___Wp of1m2

Calculation Acc.To 5Hours OfPeekSunshine

3750 Whd 1500 Wh 1500 Wh 750 Wh ___ Daily Wh

Calculation For A10m2

Roof TopSystem

Cost $ 8500

7500 WP3000 Wp 3000 Wp 1500 Wp $1000

Cost of10m2 multisolar system

Calculation For 5Hours OfPeekSunshine

37500 Whd 15000Whd

15000 Whd 7500 Whd ___Daily

KWp for10 m2

From the table; � The system is capable of producing 37,500 kWh per day � The total cost of a system, including building is $8,500. � Over the next 10 years such a system will produce energy at $ 0.0625 per kWh. $8500 initial

investment, 37500 Whd x 365 days x 10 years

� It is safe to estimate that the system will be functioning for 20 years hence the price per kWh is halved,3 (three) cents. A price per kwh that is cheaper than any other energy source.

Comparative costs benefitsBetween

1. A solar thermal water heating system, DHW.2. A photovoltaic system, PV.

3. A combined, thermal water and space heating and PV system.A “MULTI SOLAR SYSTEM”, MSS.

DescriptionDHW SystemCost in US $

PV SystemCost in US $

MSSCost in US $

Collector,Box & Frame

100 100 100

Glass, 2 X CR-120 160 --/-- --/--600w PV Panel --/-- 3200 2800Battery Cable --/-- 39 39Electricity & WaterAccessories

--/-- 39 39

Battery --/-- 750 750Electricity Box --/-- 170 1702.5 Watt Inverter --/-- 1000 100060A Controller --/-- 200 200200 Liter Tank 170 --/-- 170Collector Stand 42 42 42Labor: 2 XTechnicians

157 157 157

Installation Charge 373 373 373

Total $ 1002 $ 6070 $ 5840$ 7072

ENERGY OUTPUTSDHW kcal PV System Wp MSS kcal and Wp

Thermal 12000 --/-- 5000 + 8000kcalSpace + water

Electrical --/-- 450 Wp 550 WpTotal OutputDaily

12000 kcalHot water

1.5-2.5 kWhdailyElectricity

13000 kcalspace water 2.0 = 4.0kwh

daily Electricity

From this table it is clear that the multi solar system (“mss”) cost less than any other solarsystem and produces more electrical energy and hot water and space heating for free