Getting the renewable energy mix right

I was out at Desert Mirage High School in Thermal on Wednesday, talking with students in the school’s green tech career academy about what I do as an energy and green tech reporter — ask people a lot of questions about very technical things and try to turn it all into plain English.

Most of the students said they want to work in a green tech or engineering field, so I also spoke about the importance of good communication skills and the inestimable value of being able to write clear, grammatical sentences (old school, I know, but it’s something I’m actually rather passionate about).

One of the students asked me what I thought the best form of renewable energy is, and I stopped for a second. Being a reporter, one always stops when anyone asks you what you think the best of anything is, because one cannot appear to be biased or endorsing one thing over another.

Luckily in this case, it was not a problem. What I said, in essence, is that , with renewable energy it isn’t a matter of better or worse, but rather how the different forms fit together and complement each other.  We need them all.  The wind blows best at night — so we can have renewable energy on the grid ready to go in the wee hours and early morning.  Then photovoltaic, rooftop solar comes on in the morning and peaks in the afternoon for daytime use.

Geothermal can fill in the gaps, it is 24/7 baseline power. Solar thermal technology also has the potential to fill in the intermittent gaps created by wind and rooftop. While big solar thermal projects, such as BrightSource Energy’s Ivanpah plant, have major environmental impacts and have been difficult to perimit, their technology — using solar energy to heat fluids and run a traditional generator — provides a more reliable power source than rooftop solar.

If you add storage to the picture — and it’s coming, in the foreseeable future — you have the possibility of a grid that can, at least in theory, run almost entirely on clean, renewable sources with the inevitable economies of scale and lower prices.

This is, at least in part, the argument that some advocates are now making as California develops a renewable energy portfolio that will provide 33 percent of the state’s power by 2020. The utilities have largely loaded up on cheaper photovoltaic projects that by their very nature mean we will need some kind of fossil fuel backup to balance the intermittency of solar.

More reliable forms of renewables, such as solar thermal, are more expensive, but cost alone should not be the only factor considered.

Which brings me to BrightSource. Even as the company’s Rio Mesa project looks shaky – possibly losing a power purchase agreement to sell half the power from the plant and facing millions in mitigation costs to offset environmental impacts — investors have given the company a vote of confidence in the form of $80 million in new equity funding.

In a press release issued today, company executives announced a list of new investors –

Alstom, a global leader in the world of power generation, and VantagePoint Capital Partners lead the round. Additional investors include DFJ, CalSTRS, DBL Investors, Goldman Sachs, Chevron Technology Ventures and BP Ventures among others.

The company now has $615 million in equity funding.

Alstom is a French energy multinational and VantagePoint is a major player in clean tech investments. That major fossil fuel companies such as Chevron and BP want in also speaks volumes.

The bottom line is, every form of energy, whether fossil fuel or renewable, has some kind of environmental impact; that is the unavoidable trade-off we make for the power.

Figuring out the best value and right balance of renewables going forward will be a complex process, involving careful thought and calibration of lots of competing and conflicting factors.  Hopefully, some of the students I spoke with today will help find the solutions.

And they’ll be able to write about it in clear, grammatical sentences.