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SOLAR ENERGY FOR THE GREEN ECONOMY:
IS IT AN EXPENSIVE WASTE OF TIME,
OR A SMART STRATEGY? Anders Jepsen, CEO, Heliodynamics,
Inc. for the
Santa Fe Community CollegeSustainable Technologies Center
25 June 2008
SFCC Green Energy Workshop
25 June 2008- 2
Climate Change -Somebody Else’s
Problem?“We will pay for this one way or another. We will pay to reduce greenhouse gas emissions today, or we will pay the price later in military terms.”
General Anthony C. Zinni, USMC (Ret.), Former Commander-in-Chief of U.S. Central Command (CENTCOM)
SFCC Green Energy Workshop
25 June 2008- 3
Climate Change is an Energy Problem
•Almost all of it is caused by burning fossil fuel.
•Most of our energy (electricity, heat and motive power) comes from burning fossil fuels.
•The fossil fuel industries are firmly entrenched in our way of life.
SFCC Green Energy Workshop
25 June 2008- 4
The 21st Century Energy Challenge• An irresistible force:
Rising energy demand to increase the size of the world economy;
China’s demand has required an increase in oil supply.
• An immovable object: Not enough growth in energy supply.
• Result: Price of oil risen 1200% in a decade; Price of fuels has doubled in 10 months.
SFCC Green Energy Workshop
25 June 2008- 5
6-month natural gas curve
SFCC Green Energy Workshop
25 June 2008- 6
Why is supply not keeping pace? -1
•Oil: 75% capacity is under control of
government monopolies;
Both of the world’s largest oil fields, Saudi Arabia’s giant Ghawar field and Kuwait’s giant Burgan field, are in decline;
SFCC Green Energy Workshop
25 June 2008- 7
Why is supply not keeping pace? -2
Natural Gas:
More capital investment & time required to develop infrastructure.
Coal:
Until carbon emission problem is solved, new investment in coal-fired power plants very unlikely.
SFCC Green Energy Workshop
25 June 2008- 8
What will balance supply and demand?
•Reduction in Demand(either by energy conservation or by
industries forced to close by energy costs):
Vehicles (oil);
Buildings (coal, gas);
Processes (gas).
SFCC Green Energy Workshop
25 June 2008- 9
Whose demand may stabilise price?
•Countries which subsidise fuels? - No
China; India; Most of the M. East.
•Market economies? - Yes
IF taxes not reduced on motor fuels; IF technologies offer improved performance.
SFCC Green Energy Workshop
25 June 2008- 10
What other options do we have to meet the need for new supply?
•Other sustainable (renewable) sources of energy: Biofuels (cellulose, sugar, seed-oil); Wind; Solar; Marine.
SFCC Green Energy Workshop
25 June 2008- 11
So, where does HelioDynamics fit into this scenario?
•We’re a concentrating solar technology company.
•We make systems to deliver industrial grade heat for solar-powered air conditioning and for other processes that now burn natural gas
•We make Combined Heat and Power (CHP) systems for both electricity and heat for many different uses.
Concentrating Solar
So what’s Concentrating Solar?Big area of focus or reflector, small area of receiver Existing systems use the heat to make electricity
Solar 2 (tower, decom’d) SEGS (trough, working) Dish Stirling (in dev)
How do these Concentrating Solar systems harvest the heat energy?
ReceiversTower (molten salt!) from reflecting heliostats
heat to steam to turbine electricityThermal tubes of hot oil – from reflecting troughs
heat to steam to turbine electricityDish Stirling – Stirling engine drives a
turbine directly. 25kW per unit.
What’s good about these systems?
1) Utility Scale Concentrating systems can and do deliver solar power to the grid
2) Lots of sunny (windy) desert space available
But, here’s the down side.
1) The technology needs big systems to work - very costly
2) Big arrays need extra wheeling capacity (power lines) to deliver the power to the grid.58
395
SFCC Green Energy Workshop
25 June 2008- 15
Is there a smaller technology?
Yes, indeed! Here’s a simple system:* a linear Fresnel lens, made from* flat plate glass mirrors* laser-cut steel or aluminum structure* a single controller to keep the sun focused, and* makes pv electricity and heat together, or just heat
It works just like the big systems - big area of reflectors, small area of receiversHow does it make the electricity? The system has the pv cells, modified so they can carry a lot of current, mounted to the underside of the receiver. We cool the pv cells so optimize their performance,and the cooling system harvests the heat
That’s Combined Heat and Power! CHP
CHP not only uses PV cells to make electricityby concentrating the the sun but also makes heat, at the same time!
And, because of its simplicity of design, it can be installed anywhere that the energy is needed. It’s DISTRIBUTABLE!
And what about the heat?
That’s where the real energy savings come in.If you have a use for the heat, the capital cost barrier that has stood in the way of solar power for all these years IS REMOVED.
So how can we use the heat?Community power, cooling and heatHot water for hospitals, labs, industriesDrive a Chiller for refrigeration and coolingHot water for schools and gymnasiaWhat do you need? What do you
want?
So where does CHP fit in today’s world?
Three configurations available:
Heat only – receiver has no pv cells, industrial grade heat up to 225 C Electricity only – GaAs cells, 500x conc’n. Coming soon for large energy parks Combined Heat and electric Power (true CHP: Electricity + 90C hot water)
(presently limited by pv cell shortage)
Some Applications
• Off grid mobile home park in Napa Valley
• Food processor• Hospital hot water• Retirement Community air conditioning• Albuquerque airport car rental facility
Mobile Home Park: CHP
Long term Object: 500 kWe, LEEDS certification, community heating (propane now) and community air conditioningStart with: 10 kWe plus
60 kWthermUse for heat: air conditioning, winter heating and pasteurization for ag useLocal value of the electricity: @$.30 per kWe =$6000yrLocal value of the heat: @$4.40/therm =$17,600/yr
Food Processor – Refrigeration(and hot water for cleaning)
Objective: Refrigeration and hot waterObstacle: CFO, paybackMotive: Save $ nowTechnical: replace 50 tons elect refrig’n plus 1.6MMBTU/hr hot waterValue: Replace 116,600 kWe/yr 35,400 therms gas/yrCost: $700,000, payback 3.5 years
Hospital – hot water
Objective: hot waterObstacle: paybackMotive: hedge against ga$; Look greenSize: 1287 kW therm over pkg lotCost: $1,100,000Payback: 11 yrs w/ FTC (before gas price increase)
Retirement Community – Cooling
Objective: Provide A/C cooling to individual unitsObstacle: CFO, paybackMotive: look green & Hedge against gas $Size: 450 tons of coolingCost: $3.4 millionPayback: 7 yearsIncentives: FTC, 5-yr dep’n
Albuquerque Airport - CHP
System: 30 tons refrigeration (105 kW cooling) equivalent to 35 kWe of electricity plus 13 kWe
Site: SunPort car rental
Output: 48 kWe (equiv)
Cost: $6.00 per watt!
SFCC Green Energy Workshop
25 June 2008- 25
Answer(1): We developed a two-axis system
using GaAs pv cells and a greater optical concentration – 500 suns
Question: So, how did we adapt this technology to bigger, utility-scale systems?
~7.5m
~4m
Azimuth Tracking
HD GaAs 2 Axis Concentrator
3-5-5-3 Module Array on ~30m Turntable.
Output: 48kWe (DC)
Primary Optics : Cradlesx15kW/m2
Secondary optics:Parabola x200 kW/m2
Tertiary optics: Lensx750 kWm2
Space Need: 5 acres per MWe
Cradles
SFCC Green Energy Workshop
25 June 2008- 27
Answer(2): We adapted our HD16.t single-axis system with higher performance fittings on the thermal receiver to generate up to 225C heat.
This is hot enough to drive an Organic Rankine Cycle (ORC)
120kWe turbine.
and another adaptation…
SFCC Green Energy Workshop
25 June 2008- 28
Again, 1 MWe on 5 acres, $6 per watt today,with both electric power and heat!
• Multiple arrays of HD16.t, yielding heat at 225C
ORC Turbogenerator
Invertor/controller
Chop/dry
Nickel metal
chloride battery
Woodfuel
Thermalsolar
concentrator
Sun
Demand controller/
meter
Boiler
Shop: appliances, meter top-up, advice
LocalGrid
Layout of complete system with wood burning backup for extended operation beyond solar hours
SFCC Green Energy Workshop
25 June 2008- 29
A LocalGrid Integrated Schematic
ORC Turbogenerator
Inverter
Fuel dryer (opt)Nickel
salt battery
Chipped woodfuel
Sun
CustomerService
Unit
Boiler BiodieselGenerator
Sets
Biodiesel
Solar PV
SFCC Green Energy Workshop
25 June 2008- 30
So, a Quick Recap
Solar Technology: simple design that’s a candidate for local manufacture (much of it, anyway).
Applications:Solar Powered Air ConditioningCombined Heat and Power for Commercial/IndustrialStand-Alone off-grid systems with other renewablesCan be scaled up for grid scale production
Solar is becoming cost competitive as well as being green
SFCC Green Energy Workshop
25 June 2008- 31
It doesn’t seem like such a waste of time after all!
Thank you for your attention
Anders Jepsen, CEOHelioDynamics, Inc.23 Dos PososOrinda, CA 94563
tel: 1-925-254-5250