Here are the constituents of the WilderHill Clean Energy Index, with a brief description of each company, as of April 1st 2006. The index is the basis for the PowerShares WilderHill Clean Energy Portfolio ETF (PBW).
Renewable Energy Harvesting - 27% sector weight (10 stocks @2.7% each)
Distributed Energy, (DESC). Part solar, wind; mainly in DG, some H2: an integrator.
Emcore, (EMKR). Solar, 27% ultra-efficient PV cells, also makes LED products.
Evergreen (ESLR). Unique string-ribbon solar PV with efficient silicon-use.
Kyocera, (KYO). Solar PV, integrated manufacturer is doubling production.
MEMC, (WFR). Producer of the polysilicon needed in many crystalline solar PV cells.
Ormat, (ORA). Geothermal, works as well in recovered energy, biofuels.
SunPower, (SPWR). Solar, Efficient PV panels with all-rear-contact cells.
Cypress, (CY). (Parent firm of SPWR above, and owns the major block of their stock).
SunTech Power, (STP). Solar, fast-growing and major producer of PV is based in China.
Zoltek, (ZOLT). Wind, makes carbon fiber for wind blades and product ‘lightening’.
Power Delivery and Conservation - 26% sector weight (10 stocks @2.6% each)
American Superconductor, (AMSC). Superconductors, ‘no’-resistance 2G HTS wire.
American Power Conversion, (APCC). UPS, makes firm-power systems.
Cree, (CREE). LEDs, makes efficient lights, power-saving electronics.
Echelon, (ELON). Networking, for management of whole energy systems.
International Rectifier, (IRF). Efficiency-enabling electronics producer.
Itron, (ITRI). Monitoring, designs energy measurement and management systems.
Magnetek, (MAG). Makes solar inverters, wind power converters, power controllers.
Power Integration, (POWI). Energy savings, enables power conservation in IC chips.
SuperPower / Intermagnetics, (IMGC). Superconductors, and power transmission.
UQM Technologies, (UQM). Hybrid vehicle electrics; motor & power systems.
Energy Conversion - 18% sector weight (7 stocks @2.57% each)
Ballard Power, (BLDP). Mid-size fuel cells, makes mainly PEM FCs.
Capstone Turbines, (CPST). Micro-turbines 30-60 kW, may be flexible-fueled.
FuelCell Energy, (FCEL). Large fuel cells as stationary high-temp. flex-fuel MCFCs.
Hydrogenics, (HYGS). Fuel cells and testing gear, H2 electrolysis, regenerative FCs.
Medis, (MDTL). Micro fuel cells, designed for liquid-fuels and a unique electrolyte.
Mechanical Technology, (MKTY). Small fuel cells, may compete with Li-Ion batteries.
Plug Power, (PLUG). Mid-sized fuel cells for distributed generation, home power.
Energy Storage - 16% sector weight (6 stocks @2.66% each)
Active Power, (ACPW). Flywheel power storage, a firm power alternative to batteries.
Energy Conversion Devices, (ENER). Very diversified: in batteries, solar PV, also H2 FCs.
Impco, (IMCO). Gaseous fuels, a manufacturer and integrator for cleaner-fuel vehicles.
Maxwell, (MXWL). Ultracapacitors, a battery alternative such as for hybrid vehicles.
Quantum Fuel, (QTWW). Hydrogen gas storage systems for cleaner-fuel vehicles.
Ultralife Batteries, (ULBI). Batteries, advanced lithium ion, polymer rechargeable.
Cleaner Fuels - 9% sector weight (5 stocks @1.8% each)
Air Products & Chemicals, (APD). Hydrogen, a supplier of many industrial gases.
BOC Group, (BOX). Hydrogen, a supplier of many industrial gases.
MGP, (MGPI). Biofuels, ethanol and fuel alcohol.
Pacific Ethanol, (PEIX). Aims to be a leading biofuels producer for Western U.S.
Praxair, (PX). Hydrogen, a supplier of many industrial gases.
Greener Utilities - 4% sector weight (2 stocks @2.0% each)
Source: PowerShares WilderHill Clean Energy Portfolio home page.