NET METERED NET METERED PHOTOVOLTAIC (“PV”) PHOTOVOLTAIC (“PV”)

SYSTEMS IN HAWAIISYSTEMS IN HAWAII

Andy KeithAndy KeithSenior Environmental Senior Environmental

ScientistScientistHawaiian Electric Company

543-4523andy.keith@heco.com

BEFORE CONSIDERING PVBEFORE CONSIDERING PV

Energy Conservation. It’s approximately 5 times cheaper to save energy than to make it. Consider energy-efficient lighting, appliance upgrades and similar improvements.

Solar Hot Water. Simple, proven technology. Tax credits and HECO rebate ($1000) are available. Net out-of-pocket expense ~$1500. Or, check out the new Solar Saver Pilot Program. See heco.com or call 94-POWER for details.

NET METERING: The Financial NET METERING: The Financial Key to Grid-Interactive Key to Grid-Interactive

Renewable EnergyRenewable Energy Customer enters Net Energy Metering

Agreement with HECO (often, this is handled by the installing contractor)

Customer is “compensated” for energy generated by offsetting electric use. Monthly minimum charges apply.

“Net Excess Generation” may be “banked” for up to 12 months. Thereafter, it reverts to the utility.

TYPES OF GRID-INTERACTIVE TYPES OF GRID-INTERACTIVE PV SYSTEMSPV SYSTEMS

Battery-Based Inverters / Systems– Provide instant back-up power to connected loads during

utility outages. Effectively, is a UPS– More complicated to install, maintain and operate– Compatible with time of use (TOU) metering rates

Batteryless Inverters / Systems– Simpler & less expensive to install and maintain– Slightly higher operating efficiency than battery-based

systems– During utility outages, batteryless systems effectively “go to

sleep”, providing no backup capability– Central and distributed inverters are available

TYPICAL BATTERYLESS TYPICAL BATTERYLESS INVERTER SETUP (Central INVERTER SETUP (Central

Inverter)Inverter)

DISTRIBUTED INVERTER DISTRIBUTED INVERTER (Enphase Micro Inverter)(Enphase Micro Inverter)

EXAMPLE SDHW & PV EXAMPLE SDHW & PV INSTALLATIONINSTALLATION

FINANCIAL INCENTIVESFINANCIAL INCENTIVES

35% State Tax Credit ($2250 SDHW limit, $5000 PV limit)

30% Federal Tax Credit ($2000 SDHW limit; no PV limit)

“Stacking” of the two tax credits is permitted

I’M INTERESTED! WHAT’S I’M INTERESTED! WHAT’S NEXT?NEXT?

Got south-facing roof? Is it unshaded during prime sun hours?

Learn more about the technology. Surf the web. Consider subscribing to Home Power magazine (see their website at www.homepower.com)

Battery-based or batteryless technology? Begin exploring system sizing. Remember:

reduce energy use first

CALCULATING PV SYSTEM CALCULATING PV SYSTEM ENERGY PRODUCTIONENERGY PRODUCTION

Module Rating (Total) x Average Estimated Sun-Hours Per Day = kWh Produced

Example:

4.5 kW x 3 Hours = 13.5 kWh/day

LOGISTICAL LOGISTICAL CONSIDERATIONSCONSIDERATIONS

Weight of PV modules & mounting equipment is typically 3 - 5# / ft2

Power density is ~10 watts / ft2

Consider performing roof repair/replacement before installing PV (or solar hot water).

“Raw” (tax considerations excluded) installed cost is typically $8 - $10 / watt

Need to enter into a Net Energy Metering Agreement with HECO. Most common stumbling block: no building permit was obtained for the PV system

WHAT’S ON THE PV WHAT’S ON THE PV HORIZON?HORIZON?

New technologies for modules: thin-film, emerging materials (such as “shade cloth”).

Increasing emphasis on building-integrated PV (“BIPV”). Currently-available products are a) “peel and stick” for standing-seam roof systems, and b) three-tab shingle.

Absent new technologies, expect gradual price reduction as economies of production are realized.

For general information on RE, see www.hawaiisenergyfuture.com

BIPV: PARKING SHADE BIPV: PARKING SHADE STRUCTURESTRUCTURE

BIPV: DEPOT SKYLIGHTBIPV: DEPOT SKYLIGHT

BIPV: STANDING SEAM BIPV: STANDING SEAM ROOFINGROOFING

BIPV: SOLAR SHINGLESBIPV: SOLAR SHINGLES

KGMB-9 InterviewKGMB-9 Interview

With Brooks Baehr (05/20/08)

HonoluluHonolulu Advertiser Advertiser• July 13, 2009 “Bright Idea” (Mike Gordon)

http://www.honoluluadvertiser.com/article/20090713/GREEN02/907120382&template=greenhouse/Bright+idea