Interview with Ronal Larson, Chairmen of The American Solar Energy Society (ASES) - 6/03/06

RWL:   I am a retired PhD EE, who started in solar/RE in 1973 as a Congressional Fellow – on sabbatical from Georgia Tech.  I was at SERI (now NREL) for its first 5.5 years - mostly doing analysis, budget and policy work.  After some solar work for USAID in Sudan, I was mostly retired from renewable energy activities until I became active in forming the Colorado Renewable Energy Society (CRES) about 1996.  This got me to the Board of the American Solar Energy Society (ASES) and then later I was elected as its Chair.  Much of my recent renewable energy experience comes from being an active renewable energy intervener for CRES in several dockets before the Colorado PUC – and then in designing a solar home that is built around the University of Colorado’s winning entry in the 2002 national Solar Decathlon competition.

How many years are we away from a net zero energy home?

RWL:  By this I think you mean a common choice for the average US new home purchaser.  I would guess that this will happen first in the high electricity cost states like Hawaii, Alaska, California - in about 10 years.  Because of our low energy prices, Colorado will lag by 5-10 years, unless our incentives for solar thermal grow; right now they are pretty good for solar electric.   Zero energy homes will come about mostly because of cost reductions in PV as cumulative production grows.  I gather CA is pretty close now - with a waiting list for their rebates.  Japan is already there with its > 15 C/kWh.  The house I live in is a net zero energy home.

What are the technology challenges facing more efficient solar photovoltaics or PV?

RWL:  I sense you are putting the emphasis on "efficiency" vs "cost", which of course are different.  Re cost, I think we are mostly going through a typical experience (or learning) curve growth period.  Bigger factories will make a huge difference.  With a PV production doubling time of two years or less (much driven by Germany and Japan) we are in excellent position to have the needed cost reductions within the next ten years.  As to efficiency, I guess the answer might lie with greater nano-technology development.  When I hear high efficiency, it seems to also depend on nanostructures - where we are spending a pitiful amount of funding

What role will solar play in vehicle integrated PV applications for charging hybrid electric vehicles?

RWL: This will be a major factor in PHEVs.  The May-June issue of ASES’ Solar Today magazine had two excellent (free-to-download) articles on this.  (http://www.solartoday.org/current_issue.htm). This last week, for the first time, I have seen considerable dialog on the topic of on-board PV - and believe that also will begin to happen commercially within a decade – when battery costs have declined enough. The economics are apparently strongly in favor of Vehicle Integrated PV (VIPV) - but the Federal (probably also international) funding is zilch.  I wrote something on the 28th that can be seen at http://www.energypulse.net/centers/article/article_print.cfm?a_id=1267#jump_

With increased demand for solar power do you see photovoltaics going down in price?

RWL:  Absolutely.  We shouldn't be even considering PV if huge cost reduction hadn't already happened and more virtually guaranteed.  I see no reason not to continue the historic 20% reduction curve, for maybe 4-5 more doublings, when it might dropp off some.  I wrote on this in my March-April Solar Today "Chair's Corner" - on how cost and demand and past rapid growth are all intimately tied together.  It is critical that advocates talk about future cost reductions.  The main justification for small PV subsidies is this promise of future low costs.

Your website states it is cost effective anywhere in the U.S. to heat water using a solar thermal system.  How long does it take to pay for this type of system on the average?

RWL:  I guess you are referring to www.findsolar.com.  The costs there are strongly dependent on where one lives.  The new $2k from the Feds will help a lot.  But I would say for DSHW, an average payback time could be in the 3-year range.   But with proper financing, there can be savings in the first month, as higher mortgage payments are lower than the previous energy bills.  In addition, the solar investment results in a higher resale value for the home.

Are there any tax incentives to the home owner to purchase a solar system?

RWL:  Of course the new Fed 30%  tax credit appplies to both PV and Solar Thermal.  Going to the "DSIRE" data base and to www.findsolar.com will show many other state and local incentives.  In Colorado, our Amendment 37 rebate (not a tax incentive) is huge for PV.  I think CA has a smaller rebate, but just as good economics because the cost of electricity is much higher on average.

Efficient battery technology is an important part of a PV system.  Do you believe there will be technology breakthroughs in battery technology in the near future?

RWL:  Absolutely.  Being driven by the need for better batteries for portable computers.  It is a national crime that Federal battery research has fallen to such low levels. The strong public acceptance of hybrids (I own two) will help greatly in battery development and cost reduction for PV – both for the home and the vehicle.

How would a home owner calculate the cost effectiveness of purchasing a solar system based upon what they currently pay for electricity?

RWL:  I watched the development of www.findsolar.com fairly closely and think that the costing methodology there is pretty good.  A key variable, often overlooked, is the added value of the home.  One must consider this as an investment - not just an expense.  Going to several installers is an important first step to verify the average results one can obtain from the findsolar site.

Do you believe the average American would be receptive to joining a Renewable Community?

RWL:  Probably not yet the "average" - but co-housing is growing in popularity in Colorado.  It will be more so as Peak Oil really arrives - and will move faster as soon as a carbon tax is enacted (in part because seasonal thermal energy storage is more practical in larger sizes.)

Do you see photovoltaics made from organic chemicals using nanotechnology having a place in solar energy?

RWL:  Absolutely - as stated above.  But I would make these two separate questions.  I have not heard that organic chemical approaches have to involve nanotechnology.  And nanotechnology need not involve organics.  This is rather outside my area of expertise.  It is great to see your organization getting so involved in renewables (and especially the residential solar side) from concern about fossil fuel availability.  But we need to couple the resource depletion arguments with national security, global warming, health, and economic development rationales as well.  The recent growth in the solar/RE industry has been fantastic – but we are just beginning.

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