Thanks to SunPower’s technology and this unique energy generation project, we’re realizing significant cost savings in our utility bills.”

– Carl A. Carlson, Jr. President, Parker Ranch


Parker Ranch is one of the largest and most historic cattle ranches in the country, spanning over 225,000 acres across the Big Island of Hawaii. It surrounds the town of Waimea and spreads between the Kohala and Mauna Kea mountains. The net income of Parker Ranch goes to the Parker Ranch Foundation Trust for the benefit of four local charities: North Hawaii Community Hospital, Hawaii Preparatory Academy, Parker School Trust and Hawaii Community Foundation.


Today’s businesses are faced with considerable energy challenges: rising costs of traditional energy sources, limited supplies and environmental pressures. Hawaii and Parker Ranch are blessed with exceptional renewable energy resources. By tapping the unlimited energy of sun and wind, Parker Ranch could create the largest hybrid solar/wind electrical generating system in the world, and reduce its electricity costs efficiently, in harmony with the landscape.


Recent advances in photovoltaic (PV) technology have made onsite commercial solar power generation a viable, clean source of renewable energy. Parker Ranch chose SunPower to design, manufacture and install a PV system to operate in tandem with wind generators. Covering approximately two acres, this hybrid project generates 175 kW of photovoltaic power and 50 kW of wind power. The Parker Ranch project is equipped with SunPower’s T0 Tracker solar electric system. This ground-mounted power array rotates its solar panels to follow the sun from east to west, generating the maximum energy possible. Additionally, five wind turbines were constructed onsite to augment the energy provided by the PV array. Wind and solar power compliment each other because the wind turbines can produce energy at night when the PV array is inactive.

Photovoltaic System Description

Parker Ranch’s photovoltaic (PV) system can produce up to 209 kW under peak sun conditions. The system array is made up of 476 photovoltaic modules arranged in17 rows of 28 modules, and rotates on a single axis to track the motion of the sun.This tracking allows the system to produce up to 29% more energy than a stationary array of the same size.

The solar electric system installed at the Parker Ranch is a single-axis tracking array. The photovoltaic modules compromising the system contain solid-state semiconductors that convert sunlight into direct current (DC) electricity. DC output from the PV modules is converted to 208 Vac by means of a 185 kVA inverter, and then stepped up in voltage by a 225 kVA transformer to match the local utility grid voltage, which transports the electricity produced to operate remote livestock watering pumps.

Emissions Savings

By avoiding the purchase of fossil-fuel generated electricity, Parker Ranch’s solar electric system spares the environment from thousands of tons of harmful emissions such as nitrogen oxides, sulfur dioxide and carbon monoxide, which are major contributors to smog, acid rain and global warming. It is estimated that over the25-year lifetime of the photovoltaic system, the solar-generated electricity will reduce emissions of carbon dioxide by 6,207 tons.

Project Overview

System Type:    Ground System
Location:    Kameula, HI
Date Completed:    January 2001
System Peak Capacity:    209 kW
System Area:    20,000 square feet
Solar Electric Tiles:    5,824
Products:    SunPower® T0 Tracker


On any given day, the combination of sun and wind provides enough power to runall the pumps delivering drinking water to Parker Ranch’s livestock in the Mauna Kea,Mana and Keamuku graving areas. Money saved from reduced utility bills more thancovers the amortized cost of the solar energy water pumping system. Over the life ofthe project, this system will produce enough clean power to avoid the use of 70,000barrels of imported oil — this will spare Hawaii’s environment from thousands ofpounds of harmful emissions including NOx, SOx and CO2. By harnessing thenatural energy solution and conserving natural resources.