From new bike paths and electric-car chargers to an aggressive "green building" code and a "carbon neutral" electric supply, Palo Alto has no shortage of green laurels on which it can rest.

But with climate change taking on a greater urgency around the globe and the issues of water conservation and traffic congestion dominating conversations closer to home, the city's green agenda is expected to only grow in the coming years as officials prepare to adopt additional carbon-cutting goals and launch new programs aimed at getting people out of their cars and boosting the use of renewable energy.

What exactly will this look like and how far should the city go? These are the questions that the city hopes to explore in the coming days, as it hosts a community summit devoted to sustainability and a public hearing on the city's new and Climate Action Plan.

Both the summit, which will take place at 12:30 p.m. Sunday at Jordan Middle School, and the new sustainability plan, which the City Council will discuss on Monday, are the brainchildren of Gil Friend, the city's first chief sustainability officer. Since joining the city two years ago, Friend has been gathering ideas from experts, other cities and community stakeholders for the broad document, which remains a work in progress. During Sunday's Climate and Sustainability Summit, residents will have a chance to weigh in and offer their own ideas about what types of goals and green initiatives the city should pursue (or avoid).

For example, should Palo Alto aggressively encourage homes to convert their heating systems from natural gas to electricity? Should it start charging people for parking in downtown Palo Alto and then use the money for green initiatives? Should the city aim to reduce its carbon footprint by 80 percent (when compared with the 1990 level) or pursue an even more ambitious "moonshot" goal of complete carbon neutrality?

These questions, and many others, will be explored during the summit and Monday's City Council meeting, which will also give residents and council members a chance to influence the plan. The goal of the summit, Friend said, is to "open up a broad community conversation about our draft plan and opportunities."

The city's recent history offers plenty of promise. In 2007, the City Council adopted the city's first Climate Protection Plan, which called for a 15 percent reduction in the city's greenhouse-gas emissions by 2020. The city has easily cleared this goal, reducing its emissions by an estimated 32 percent from 2005 levels and by 37 percent from the 1990 levels.

Now, officials are looking ahead to new goals, with more aggressive targets, inspired by municipalities around the world. California has an aspirational goal of reducing its emissions by 80 percent from the 1990 levels by 2050. Copenhagen has adopted a plan to be carbon neutral by 2025 and to have 75 percent of the residents to use bikes to get to work and school, according to a report that Friend presented to the council last year. Helsinki hopes to be car-free by 2025. Burlington, Vermont, has a 100 percent renewable energy supply, and Fort Collins, Colorado, has a goal of reducing its greenhouse-gas emissions by 80 percent (from the 2005 levels) by 2030.

Last spring, Friend presented to the council several potential goals for the new sustainability plan, which will aim to "create a prosperous, resilient city for all residents," according to his report.

Now, staff is favoring an 80 percent reduction by 2030 (what's known as 80x30), a goal that may seem ambitious but that Friend believes is very attainable in a city like Palo Alto. Friend noted that the city has already reduced its emissions by nearly 40 percent since the 1990 level and that most of these green initiatives actually kicked off around 2005. This means that the community has effectively achieved the 40 percent reduction in just nine years.

Not that anyone expects it to be easy. While the city's Utility Department reached a rare milestone in 2013 when it achieved a carbon-neutral electric portfolio, transportation and natural gas continue to pose formidable challenges.

"To get to the California goal of 80 percent reduction in 2050 or anything more dramatic, we clearly have to transform transportation and our relationship to natural gas," Friend said.

Palo Alto has several key advantages in addressing these challenges, he said. These include an incredibly educated community and a carbon-neutral electricity portfolio, which could help the city address the transportation quandary. The city, he said, can help accelerate the electrification of the city's vehicle fleet by providing more charging stations. It can also take a fresh look at parking pricing, a subject that will be explored in a study that the City Council commissioned last week.

"We incentivize the automobile by having free parking," Friend said. "Other communities don't do that. Should we continue to do that or not?"

The Sustainability Summit will include a keynote address from U.S. Marine Col. (ret.) Mark Mykleby, founding director of the Strategic Innovation Lab at Case Western University and former strategic assistant to the chairman of the Joint Chiefs of Staff on the role of climate change in America's "grand strategy." Residents will then have a chance to discuss topics such as transportation, electrification, water conservation and climate adaptation in small groups.

Whether residents choose to enthusiastically accept or vehemently reject these proposals, staff is hoping to see some contributions of good ideas and content at the community event, Friend said.

"If we can find shared aspirations -- that we want do something significant on climate that benefits us and serves as an example for other communities, that's a good start," he said.