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Aurora Solar Blog

Landmark Solar Design: The White House

Gabrielle CosetengGabrielle Coseteng

In our new series Landmark Solar Design, we will be exploring the world, all from the comfort of the Aurora office in Palo Alto. In each post, we will ‘travel’ to a famous landmark and investigate its potential for solar energy generation.

For each site, we will go through the entire solar design process - from determining an optimal component layout based on the roof structure and shading losses all the way to a cost analysis with various financial options.

With election season in full swing, we couldn’t think of a more appropriate site than the White House for the inaugural post of our series. We have prepared a preliminary site assessment and proposal for President Obama to look at in the last few months of his term (or the National Parks Service since they’re in charge of maintaining the White House grounds).

A brief history of solar energy at the White House

Jimmy Carter at White House solar panel unveiling President Jimmy Carter on the unveiling of his solar thermal panels in 1979.

The White House is no stranger to the benefits of solar, and has had solar systems in place since 1979.

While 6.3-kW is a typical PV size for an average American home, the White House roof has untapped solar potential that could power administrative offices and facilities in the complex. The estimated yearly electricity consumption of the White House is around 852,500kWh, based on average kWh/sq ft of office buildings.

Given the size of the building, a commercial scale installation would be appropriate. To meet those electricity needs, we found more spots for solar panels on the roof of the White House.

Analyzing the roof structure

The White House has three main sections:

The grandiose three-story executive residence has various obstructions on the roof, making it difficult to place large arrays there in our solar design. Its height also results in shading on the surrounding structures.

White House Solar Irradiance Map

The irradiance map reveals that the West Wing is a hotspot, not just for political activity but also for solar access.

Based on solar access values from nearby weather stations (TMY3), we see that East and West wings have the highest solar energy potential, followed by the unshaded regions of the East and West colonnades.

Solar system layout

Using Aurora’s autofill tool, we placed a total of 980 American-made SunPower solar modules on both wings and colonnades, for a 320-kW system. (For the colonnades, we only put solar modules where the annual solar access was more than 80%.)

White House System Design

Spec Table

System Size 320-kW
Panel Tilt 20°
Row Spacing 2.0 ft
Number of Modules 980
Estimated Project Cost $1,000,000

Simulating energy performance

White House Energy Performance Simulation Taking into account system loss factors such as soiling, snow, and shading, our performance simulation engine estimates that the solar design can produce 358,123 kWh of electricity in a year.

Electricity offset

White House Electricity Offset from Solar The solar energy production would offset almost 43% of the White House’s electricity consumption, significantly reducing its carbon footprint.

Financing options

Now, how should the United States government pay for the proposed solar system we designed?

4th of July Solar on White House Energy independence: Minimal shading across panels on the White House roof on the 4th of July

Cash Cash Payback Period White House If the White House paid for the entire system upfront, the payback period would be 11.65 years, or 2.91 presidential terms. Not ideal.

Loan Loans Payback Period White House Thankfully, the US government can get a pretty good deal with financing options. After all, federal infrastructure development isn’t quite complete without some healthy debt.

Let’s assume Uncle Sam takes out a loan consistent with its borrowing history. The loan covers 100% of the project cost and they don’t pay any dealer fees. The loan interest rate is benchmarked to the current 30 year treasury yield rates (USGG30YR:IND via Bloomberg).

That looks like a much better investment! Because we predict utility rate escalation at 3.5%, the deal only gets better as time goes on.

There you have it: Clean Energy Savings for All -- of the White House. It’s a sound business decision that would entice both Hillary and Donald.

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